2000-04-18 08:24:03 +02:00
|
|
|
@node System Management, System Configuration, Users and Groups, Top
|
|
|
|
@c %MENU% Controlling the system and getting information about it
|
|
|
|
@chapter System Management
|
|
|
|
|
|
|
|
This chapter describes facilities for controlling the system that
|
|
|
|
underlies a process (including the operating system and hardware) and
|
|
|
|
for getting information about it. Anyone can generally use the
|
|
|
|
informational facilities, but usually only a properly privileged process
|
|
|
|
can make changes.
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
|
|
|
|
@menu
|
|
|
|
* Host Identification:: Determining the name of the machine.
|
2000-05-21 23:22:28 +02:00
|
|
|
* Platform Type:: Determining operating system and basic
|
|
|
|
machine type
|
2000-04-18 08:24:03 +02:00
|
|
|
* Filesystem Handling:: Controlling/querying mounts
|
2000-04-30 22:53:48 +02:00
|
|
|
* System Parameters:: Getting and setting various system parameters
|
1995-02-18 02:27:10 +01:00
|
|
|
@end menu
|
|
|
|
|
2000-04-18 08:24:03 +02:00
|
|
|
To get information on parameters of the system that are built into the
|
|
|
|
system, such as the maximum length of a filename, @ref{System
|
|
|
|
Configuration}.
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
@node Host Identification
|
|
|
|
@section Host Identification
|
|
|
|
|
2000-04-30 22:53:48 +02:00
|
|
|
This section explains how to identify the particular system on which your
|
|
|
|
program is running. First, let's review the various ways computer systems
|
|
|
|
are named, which is a little complicated because of the history of the
|
|
|
|
development of the Internet.
|
|
|
|
|
|
|
|
Every Unix system (also known as a host) has a host name, whether it's
|
|
|
|
connected to a network or not. In its simplest form, as used before
|
|
|
|
computer networks were an issue, it's just a word like @samp{chicken}.
|
|
|
|
@cindex host name
|
|
|
|
|
|
|
|
But any system attached to the Internet or any network like it conforms
|
|
|
|
to a more rigorous naming convention as part of the Domain Name System
|
|
|
|
(DNS). In DNS, every host name is composed of two parts:
|
|
|
|
@cindex DNS
|
|
|
|
@cindex Domain Name System
|
|
|
|
|
|
|
|
@enumerate
|
|
|
|
@item
|
2000-06-02 02:27:08 +02:00
|
|
|
hostname
|
2000-04-30 22:53:48 +02:00
|
|
|
@cindex hostname
|
|
|
|
@item
|
|
|
|
domain name
|
|
|
|
@cindex domain name
|
|
|
|
@end enumerate
|
|
|
|
|
|
|
|
You will note that ``hostname'' looks a lot like ``host name'', but is
|
|
|
|
not the same thing, and that people often incorrectly refer to entire
|
|
|
|
host names as ``domain names.''
|
|
|
|
|
2000-06-02 02:27:08 +02:00
|
|
|
In DNS, the full host name is properly called the FQDN (Fully Qualified
|
2000-04-30 22:53:48 +02:00
|
|
|
Domain Name) and consists of the hostname, then a period, then the
|
|
|
|
domain name. The domain name itself usually has multiple components
|
|
|
|
separated by periods. So for example, a system's hostname may be
|
2000-06-02 02:27:08 +02:00
|
|
|
@samp{chicken} and its domain name might be @samp{ai.mit.edu}, so
|
2000-04-30 22:53:48 +02:00
|
|
|
its FQDN (which is its host name) is @samp{chicken.ai.mit.edu}.
|
|
|
|
@cindex FQDN
|
|
|
|
|
|
|
|
Adding to the confusion, though, is that DNS is not the only name space
|
2000-06-02 02:27:08 +02:00
|
|
|
in which a computer needs to be known. Another name space is the
|
2000-04-30 22:53:48 +02:00
|
|
|
NIS (aka YP) name space. For NIS purposes, there is another domain
|
|
|
|
name, which is called the NIS domain name or the YP domain name. It
|
|
|
|
need not have anything to do with the DNS domain name.
|
|
|
|
@cindex YP
|
|
|
|
@cindex NIS
|
|
|
|
@cindex NIS domain name
|
|
|
|
@cindex YP domain name
|
|
|
|
|
|
|
|
Confusing things even more is the fact that in DNS, it is possible for
|
|
|
|
multiple FQDNs to refer to the same system. However, there is always
|
|
|
|
exactly one of them that is the true host name, and it is called the
|
2000-06-02 02:27:08 +02:00
|
|
|
canonical FQDN.
|
2000-04-30 22:53:48 +02:00
|
|
|
|
|
|
|
In some contexts, the host name is called a ``node name.''
|
|
|
|
|
|
|
|
For more information on DNS host naming, @xref{Host Names}.
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
@pindex hostname
|
|
|
|
@pindex hostid
|
|
|
|
@pindex unistd.h
|
2000-06-02 02:27:08 +02:00
|
|
|
Prototypes for these functions appear in @file{unistd.h}.
|
2000-04-30 22:53:48 +02:00
|
|
|
|
|
|
|
The programs @code{hostname}, @code{hostid}, and @code{domainname} work
|
|
|
|
by calling these functions.
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
@comment unistd.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int gethostname (char *@var{name}, size_t @var{size})
|
2000-04-30 22:53:48 +02:00
|
|
|
This function returns the host name of the system on which it is called,
|
|
|
|
in the array @var{name}. The @var{size} argument specifies the size of
|
|
|
|
this array, in bytes. Note that this is @emph{not} the DNS hostname.
|
|
|
|
If the system participates in DNS, this is the FQDN (see above).
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
The return value is @code{0} on success and @code{-1} on failure. In
|
|
|
|
the GNU C library, @code{gethostname} fails if @var{size} is not large
|
|
|
|
enough; then you can try again with a larger array. The following
|
|
|
|
@code{errno} error condition is defined for this function:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item ENAMETOOLONG
|
|
|
|
The @var{size} argument is less than the size of the host name plus one.
|
|
|
|
@end table
|
|
|
|
|
|
|
|
@pindex sys/param.h
|
|
|
|
On some systems, there is a symbol for the maximum possible host name
|
|
|
|
length: @code{MAXHOSTNAMELEN}. It is defined in @file{sys/param.h}.
|
|
|
|
But you can't count on this to exist, so it is cleaner to handle
|
|
|
|
failure and try again.
|
|
|
|
|
|
|
|
@code{gethostname} stores the beginning of the host name in @var{name}
|
|
|
|
even if the host name won't entirely fit. For some purposes, a
|
|
|
|
truncated host name is good enough. If it is, you can ignore the
|
|
|
|
error code.
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment unistd.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int sethostname (const char *@var{name}, size_t @var{length})
|
2000-04-30 22:53:48 +02:00
|
|
|
The @code{sethostname} function sets the host name of the system that
|
|
|
|
calls it to @var{name}, a string with length @var{length}. Only
|
|
|
|
privileged processes are permitted to do this.
|
|
|
|
|
|
|
|
Usually @code{sethostname} gets called just once, at system boot time.
|
|
|
|
Often, the program that calls it sets it to the value it finds in the
|
|
|
|
file @code{/etc/hostname}.
|
|
|
|
@cindex /etc/hostname
|
|
|
|
|
|
|
|
Be sure to set the host name to the full host name, not just the DNS
|
|
|
|
hostname (see above).
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
The return value is @code{0} on success and @code{-1} on failure.
|
|
|
|
The following @code{errno} error condition is defined for this function:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item EPERM
|
|
|
|
This process cannot set the host name because it is not privileged.
|
|
|
|
@end table
|
|
|
|
@end deftypefun
|
|
|
|
|
2000-04-30 22:53:48 +02:00
|
|
|
@comment unistd.h
|
|
|
|
@comment ???
|
|
|
|
@deftypefun int getdomainnname (char *@var{name}, size_t @var{length})
|
|
|
|
@cindex NIS domain name
|
|
|
|
@cindex YP domain name
|
|
|
|
|
|
|
|
@code{getdomainname} returns the NIS (aka YP) domain name of the system
|
|
|
|
on which it is called. Note that this is not the more popular DNS
|
|
|
|
domain name. Get that with @code{gethostname}.
|
|
|
|
|
|
|
|
The specifics of this function are analogous to @code{gethostname}, above.
|
|
|
|
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment unistd.h
|
|
|
|
@comment ???
|
2001-02-10 17:37:51 +01:00
|
|
|
@deftypefun int setdomainname (const char *@var{name}, size_t @var{length})
|
2000-04-30 22:53:48 +02:00
|
|
|
@cindex NIS domain name
|
|
|
|
@cindex YP domain name
|
|
|
|
|
|
|
|
@code{getdomainname} sets the NIS (aka YP) domain name of the system
|
|
|
|
on which it is called. Note that this is not the more popular DNS
|
|
|
|
domain name. Set that with @code{sethostname}.
|
|
|
|
|
|
|
|
The specifics of this function are analogous to @code{sethostname}, above.
|
|
|
|
|
|
|
|
@end deftypefun
|
|
|
|
|
1995-02-18 02:27:10 +01:00
|
|
|
@comment unistd.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {long int} gethostid (void)
|
|
|
|
This function returns the ``host ID'' of the machine the program is
|
2000-04-30 22:53:48 +02:00
|
|
|
running on. By convention, this is usually the primary Internet IP address
|
1999-08-27 21:06:58 +02:00
|
|
|
of that machine, converted to a @w{@code{long int}}. However, on some
|
1995-02-18 02:27:10 +01:00
|
|
|
systems it is a meaningless but unique number which is hard-coded for
|
|
|
|
each machine.
|
2000-04-30 22:53:48 +02:00
|
|
|
|
|
|
|
This is not widely used. It arose in BSD 4.2, but was dropped in BSD 4.4.
|
|
|
|
It is not required by POSIX.
|
|
|
|
|
|
|
|
The proper way to query the IP address is to use @code{gethostbyname}
|
|
|
|
on the results of @code{gethostname}. For more information on IP addresses,
|
|
|
|
@xref{Host Addresses}.
|
1995-02-18 02:27:10 +01:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment unistd.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int sethostid (long int @var{id})
|
|
|
|
The @code{sethostid} function sets the ``host ID'' of the host machine
|
2000-04-30 22:53:48 +02:00
|
|
|
to @var{id}. Only privileged processes are permitted to do this. Usually
|
1995-02-18 02:27:10 +01:00
|
|
|
it happens just once, at system boot time.
|
|
|
|
|
2000-04-30 22:53:48 +02:00
|
|
|
The proper way to establish the primary IP address of a system
|
2000-06-02 02:27:08 +02:00
|
|
|
is to configure the IP address resolver to associate that IP address with
|
2000-04-30 22:53:48 +02:00
|
|
|
the system's host name as returned by @code{gethostname}. For example,
|
|
|
|
put a record for the system in @file{/etc/hosts}.
|
|
|
|
|
|
|
|
See @code{gethostid} above for more information on host ids.
|
|
|
|
|
1995-02-18 02:27:10 +01:00
|
|
|
The return value is @code{0} on success and @code{-1} on failure.
|
1999-08-27 21:06:58 +02:00
|
|
|
The following @code{errno} error conditions are defined for this function:
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item EPERM
|
|
|
|
This process cannot set the host name because it is not privileged.
|
|
|
|
|
|
|
|
@item ENOSYS
|
|
|
|
The operating system does not support setting the host ID. On some
|
|
|
|
systems, the host ID is a meaningless but unique number hard-coded for
|
|
|
|
each machine.
|
|
|
|
@end table
|
|
|
|
@end deftypefun
|
|
|
|
|
2000-05-21 23:22:28 +02:00
|
|
|
@node Platform Type
|
|
|
|
@section Platform Type Identification
|
1995-02-18 02:27:10 +01:00
|
|
|
|
|
|
|
You can use the @code{uname} function to find out some information about
|
|
|
|
the type of computer your program is running on. This function and the
|
|
|
|
associated data type are declared in the header file
|
|
|
|
@file{sys/utsname.h}.
|
|
|
|
@pindex sys/utsname.h
|
|
|
|
|
2000-06-02 02:27:08 +02:00
|
|
|
As a bonus, @code{uname} also gives some information identifying the
|
2000-04-30 22:53:48 +02:00
|
|
|
particular system your program is running on. This is the same information
|
2000-06-02 02:27:08 +02:00
|
|
|
which you can get with functions targetted to this purpose described in
|
2000-04-30 22:53:48 +02:00
|
|
|
@ref{Host Identification}.
|
|
|
|
|
|
|
|
|
1995-02-18 02:27:10 +01:00
|
|
|
@comment sys/utsname.h
|
|
|
|
@comment POSIX.1
|
|
|
|
@deftp {Data Type} {struct utsname}
|
|
|
|
The @code{utsname} structure is used to hold information returned
|
|
|
|
by the @code{uname} function. It has the following members:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item char sysname[]
|
|
|
|
This is the name of the operating system in use.
|
|
|
|
|
|
|
|
@item char release[]
|
|
|
|
This is the current release level of the operating system implementation.
|
|
|
|
|
|
|
|
@item char version[]
|
|
|
|
This is the current version level within the release of the operating
|
|
|
|
system.
|
|
|
|
|
|
|
|
@item char machine[]
|
|
|
|
This is a description of the type of hardware that is in use.
|
|
|
|
|
|
|
|
Some systems provide a mechanism to interrogate the kernel directly for
|
|
|
|
this information. On systems without such a mechanism, the GNU C
|
|
|
|
library fills in this field based on the configuration name that was
|
|
|
|
specified when building and installing the library.
|
|
|
|
|
|
|
|
GNU uses a three-part name to describe a system configuration; the three
|
|
|
|
parts are @var{cpu}, @var{manufacturer} and @var{system-type}, and they
|
|
|
|
are separated with dashes. Any possible combination of three names is
|
|
|
|
potentially meaningful, but most such combinations are meaningless in
|
|
|
|
practice and even the meaningful ones are not necessarily supported by
|
|
|
|
any particular GNU program.
|
|
|
|
|
|
|
|
Since the value in @code{machine} is supposed to describe just the
|
|
|
|
hardware, it consists of the first two parts of the configuration name:
|
|
|
|
@samp{@var{cpu}-@var{manufacturer}}. For example, it might be one of these:
|
|
|
|
|
|
|
|
@quotation
|
1998-06-11 23:06:58 +02:00
|
|
|
@code{"sparc-sun"},
|
1995-02-18 02:27:10 +01:00
|
|
|
@code{"i386-@var{anything}"},
|
1998-06-11 23:06:58 +02:00
|
|
|
@code{"m68k-hp"},
|
1995-02-18 02:27:10 +01:00
|
|
|
@code{"m68k-sony"},
|
|
|
|
@code{"m68k-sun"},
|
|
|
|
@code{"mips-dec"}
|
|
|
|
@end quotation
|
2000-04-30 22:53:48 +02:00
|
|
|
|
|
|
|
@item char nodename[]
|
|
|
|
This is the host name of this particular computer. In the GNU C
|
|
|
|
library, the value is the same as that returned by @code{gethostname};
|
|
|
|
see @ref{Host Identification}.
|
|
|
|
|
|
|
|
@ gethostname() is implemented with a call to uname().
|
|
|
|
|
|
|
|
@item char domainname[]
|
|
|
|
This is the NIS or YP domain name. It is the same value returned by
|
2000-06-02 02:27:08 +02:00
|
|
|
@code{getdomainname}; see @ref{Host Identification}. This element
|
2000-04-30 22:53:48 +02:00
|
|
|
is a relatively recent invention and use of it is not as portable as
|
|
|
|
use of the rest of the structure.
|
|
|
|
|
|
|
|
@c getdomainname() is implemented with a call to uname().
|
|
|
|
|
1995-02-18 02:27:10 +01:00
|
|
|
@end table
|
|
|
|
@end deftp
|
|
|
|
|
|
|
|
@comment sys/utsname.h
|
|
|
|
@comment POSIX.1
|
|
|
|
@deftypefun int uname (struct utsname *@var{info})
|
|
|
|
The @code{uname} function fills in the structure pointed to by
|
|
|
|
@var{info} with information about the operating system and host machine.
|
|
|
|
A non-negative value indicates that the data was successfully stored.
|
|
|
|
|
|
|
|
@code{-1} as the value indicates an error. The only error possible is
|
|
|
|
@code{EFAULT}, which we normally don't mention as it is always a
|
|
|
|
possibility.
|
|
|
|
@end deftypefun
|
1998-06-11 23:06:58 +02:00
|
|
|
|
|
|
|
|
2000-04-18 08:24:03 +02:00
|
|
|
@node Filesystem Handling
|
2000-05-21 23:22:28 +02:00
|
|
|
@section Controlling and Querying Mounts
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
All files are in filesystems, and before you can access any file, its
|
|
|
|
filesystem must be mounted. Because of Unix's concept of
|
|
|
|
@emph{Everything is a file}, mounting of filesystems is central to doing
|
|
|
|
almost anything. This section explains how to find out what filesystems
|
|
|
|
are currently mounted and what filesystems are available for mounting,
|
|
|
|
and how to change what is mounted.
|
|
|
|
|
|
|
|
The classic filesystem is the contents of a disk drive. The concept is
|
|
|
|
considerably more abstract, though, and lots of things other than disk
|
2000-04-18 08:48:18 +02:00
|
|
|
drives can be mounted.
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
Some block devices don't correspond to traditional devices like disk
|
|
|
|
drives. For example, a loop device is a block device whose driver uses
|
|
|
|
a regular file in another filesystem as its medium. So if that regular
|
|
|
|
file contains appropriate data for a filesystem, you can by mounting the
|
|
|
|
loop device essentially mount a regular file.
|
|
|
|
|
|
|
|
Some filesystems aren't based on a device of any kind. The ``proc''
|
|
|
|
filesystem, for example, contains files whose data is made up by the
|
|
|
|
filesystem driver on the fly whenever you ask for it. And when you
|
|
|
|
write to it, the data you write causes changes in the system. No data
|
|
|
|
gets stored.
|
|
|
|
|
|
|
|
@c It would be good to mention NFS mounts here.
|
|
|
|
|
|
|
|
@menu
|
|
|
|
* Mount Information:: What is or could be mounted?
|
2000-05-21 23:22:28 +02:00
|
|
|
* Mount-Unmount-Remount:: Controlling what is mounted and how
|
2000-04-18 08:24:03 +02:00
|
|
|
@end menu
|
1998-06-11 23:06:58 +02:00
|
|
|
|
2000-05-21 23:22:28 +02:00
|
|
|
@node Mount Information, Mount-Unmount-Remount, , Filesystem Handling
|
2001-02-09 18:02:23 +01:00
|
|
|
@subsection Mount Information
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
For some programs it is desirable and necessary to access information
|
|
|
|
about whether a certain filesystem is mounted and, if it is, where, or
|
|
|
|
simply to get lists of all the available filesystems. The GNU libc
|
|
|
|
provides some functions to retrieve this information portably.
|
1998-06-11 23:06:58 +02:00
|
|
|
|
|
|
|
Traditionally Unix systems have a file named @file{/etc/fstab} which
|
|
|
|
describes all possibly mounted filesystems. The @code{mount} program
|
2002-08-27 11:40:16 +02:00
|
|
|
uses this file to mount at startup time of the system all the
|
|
|
|
necessary filesystems. The information about all the filesystems
|
|
|
|
actually mounted is normally kept in a file named either
|
|
|
|
@file{/var/run/mtab} or @file{/etc/mtab}. Both files share the same
|
|
|
|
syntax and it is crucial that this syntax is followed all the time.
|
|
|
|
Therefore it is best to never directly write the files. The functions
|
|
|
|
described in this section can do this and they also provide the
|
|
|
|
functionality to convert the external textual representation to the
|
1998-06-11 23:06:58 +02:00
|
|
|
internal representation.
|
|
|
|
|
2000-04-18 08:24:03 +02:00
|
|
|
Note that the @file{fstab} and @file{mtab} files are maintained on a
|
|
|
|
system by @emph{convention}. It is possible for the files not to exist
|
|
|
|
or not to be consistent with what is really mounted or available to
|
|
|
|
mount, if the system's administration policy allows it. But programs
|
|
|
|
that mount and unmount filesystems typically maintain and use these
|
|
|
|
files as described herein.
|
|
|
|
|
1998-06-11 23:06:58 +02:00
|
|
|
@vindex _PATH_FSTAB
|
|
|
|
@vindex _PATH_MNTTAB
|
|
|
|
@vindex _PATH_MOUNTED
|
2002-08-27 11:40:16 +02:00
|
|
|
@vindex FSTAB
|
|
|
|
@vindex MNTTAB
|
|
|
|
@vindex MOUNTED
|
1998-06-11 23:06:58 +02:00
|
|
|
The filenames given above should never be used directly. The portable
|
2002-08-27 11:40:16 +02:00
|
|
|
way to handle these file is to use the macro @code{_PATH_FSTAB},
|
|
|
|
defined in @file{fstab.h}, or @code{_PATH_MNTTAB}, defined in
|
|
|
|
@file{mntent.h} and @file{paths.h}, for @file{fstab}; and the macro
|
|
|
|
@code{_PATH_MOUNTED}, also defined in @file{mntent.h} and
|
|
|
|
@file{paths.h}, for @file{mtab}. There are also two alternate macro
|
|
|
|
names @code{FSTAB}, @code{MNTTAB}, and @code{MOUNTED} defined but
|
|
|
|
these names are deprecated and kept only for backward compatibility.
|
|
|
|
The names @code{_PATH_MNTTAB} and @code{_PATH_MOUNTED} should always be used.
|
1998-06-11 23:06:58 +02:00
|
|
|
|
2000-04-18 08:24:03 +02:00
|
|
|
@menu
|
|
|
|
* fstab:: The @file{fstab} file
|
|
|
|
* mtab:: The @file{mtab} file
|
|
|
|
* Other Mount Information:: Other (non-libc) sources of mount information
|
|
|
|
@end menu
|
|
|
|
|
|
|
|
@node fstab
|
2001-02-09 18:02:23 +01:00
|
|
|
@subsubsection The @file{fstab} file
|
2000-04-18 08:24:03 +02:00
|
|
|
|
1998-06-11 23:06:58 +02:00
|
|
|
The internal representation for entries of the file is @w{@code{struct
|
|
|
|
fstab}}, defined in @file{fstab.h}.
|
|
|
|
|
|
|
|
@comment fstab.h
|
|
|
|
@comment BSD
|
|
|
|
@deftp {Data Type} {struct fstab}
|
|
|
|
This structure is used with the @code{getfsent}, @code{getfsspec}, and
|
|
|
|
@code{getfsfile} functions.
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item char *fs_spec
|
1998-06-15 20:12:05 +02:00
|
|
|
This element describes the device from which the filesystem is mounted.
|
1998-06-11 23:06:58 +02:00
|
|
|
Normally this is the name of a special device, such as a hard disk
|
|
|
|
partition, but it could also be a more or less generic string. For
|
|
|
|
@dfn{NFS} it would be a hostname and directory name combination.
|
|
|
|
|
|
|
|
Even though the element is not declared @code{const} it shouldn't be
|
|
|
|
modified. The missing @code{const} has historic reasons, since this
|
|
|
|
function predates @w{ISO C}. The same is true for the other string
|
|
|
|
elements of this structure.
|
|
|
|
|
|
|
|
@item char *fs_file
|
1998-06-15 20:12:05 +02:00
|
|
|
This describes the mount point on the local system. I.e., accessing any
|
|
|
|
file in this filesystem has implicitly or explicitly this string as a
|
1998-06-11 23:06:58 +02:00
|
|
|
prefix.
|
|
|
|
|
|
|
|
@item char *fs_vfstype
|
|
|
|
This is the type of the filesystem. Depending on what the underlying
|
|
|
|
kernel understands it can be any string.
|
|
|
|
|
|
|
|
@item char *fs_mntops
|
|
|
|
This is a string containing options passed to the kernel with the
|
|
|
|
@code{mount} call. Again, this can be almost anything. There can be
|
|
|
|
more than one option, separated from the others by a comma. Each option
|
|
|
|
consists of a name and an optional value part, introduced by an @code{=}
|
|
|
|
character.
|
|
|
|
|
1999-08-27 21:06:58 +02:00
|
|
|
If the value of this element must be processed it should ideally be done
|
1998-06-11 23:06:58 +02:00
|
|
|
using the @code{getsubopt} function; see @ref{Suboptions}.
|
|
|
|
|
|
|
|
@item const char *fs_type
|
1998-06-15 12:29:49 +02:00
|
|
|
This name is poorly chosen. This element points to a string (possibly
|
1998-06-11 23:06:58 +02:00
|
|
|
in the @code{fs_mntops} string) which describes the modes with which the
|
|
|
|
filesystem is mounted. @file{fstab} defines five macros to describe the
|
|
|
|
possible values:
|
|
|
|
|
|
|
|
@vtable @code
|
|
|
|
@item FSTAB_RW
|
|
|
|
The filesystems gets mounted with read and write enabled.
|
|
|
|
@item FSTAB_RQ
|
|
|
|
The filesystems gets mounted with read and write enabled. Write access
|
|
|
|
is restricted by quotas.
|
|
|
|
@item FSTAB_RO
|
1998-06-15 12:29:49 +02:00
|
|
|
The filesystem gets mounted read-only.
|
1998-06-11 23:06:58 +02:00
|
|
|
@item FSTAB_SW
|
1998-06-15 12:29:49 +02:00
|
|
|
This is not a real filesystem, it is a swap device.
|
1998-06-11 23:06:58 +02:00
|
|
|
@item FSTAB_XX
|
|
|
|
This entry from the @file{fstab} file is totally ignored.
|
|
|
|
@end vtable
|
|
|
|
|
|
|
|
Testing for equality with these value must happen using @code{strcmp}
|
1998-06-15 12:29:49 +02:00
|
|
|
since these are all strings. Comparing the pointer will probably always
|
1998-06-11 23:06:58 +02:00
|
|
|
fail.
|
|
|
|
|
|
|
|
@item int fs_freq
|
|
|
|
This element describes the dump frequency in days.
|
|
|
|
|
|
|
|
@item int fs_passno
|
|
|
|
This element describes the pass number on parallel dumps. It is closely
|
1998-06-15 12:29:49 +02:00
|
|
|
related to the @code{dump} utility used on Unix systems.
|
1998-06-11 23:06:58 +02:00
|
|
|
@end table
|
|
|
|
@end deftp
|
|
|
|
|
|
|
|
|
|
|
|
To read the entire content of the of the @file{fstab} file the GNU libc
|
|
|
|
contains a set of three functions which are designed in the usual way.
|
|
|
|
|
|
|
|
@comment fstab.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int setfsent (void)
|
|
|
|
This function makes sure that the internal read pointer for the
|
|
|
|
@file{fstab} file is at the beginning of the file. This is done by
|
|
|
|
either opening the file or resetting the read pointer.
|
|
|
|
|
|
|
|
Since the file handle is internal to the libc this function is not
|
|
|
|
thread-safe.
|
|
|
|
|
|
|
|
This function returns a non-zero value if the operation was successful
|
|
|
|
and the @code{getfs*} functions can be used to read the entries of the
|
|
|
|
file.
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment fstab.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun void endfsent (void)
|
|
|
|
This function makes sure that all resources acquired by a prior call to
|
1998-06-15 12:29:49 +02:00
|
|
|
@code{setfsent} (explicitly or implicitly by calling @code{getfsent}) are
|
1998-06-11 23:06:58 +02:00
|
|
|
freed.
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment fstab.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {struct fstab *} getfsent (void)
|
|
|
|
This function returns the next entry of the @file{fstab} file. If this
|
|
|
|
is the first call to any of the functions handling @file{fstab} since
|
|
|
|
program start or the last call of @code{endfsent}, the file will be
|
|
|
|
opened.
|
|
|
|
|
1999-08-27 21:06:58 +02:00
|
|
|
The function returns a pointer to a variable of type @code{struct
|
1998-06-11 23:06:58 +02:00
|
|
|
fstab}. This variable is shared by all threads and therefore this
|
|
|
|
function is not thread-safe. If an error occurred @code{getfsent}
|
1998-06-15 12:29:49 +02:00
|
|
|
returns a @code{NULL} pointer.
|
1998-06-11 23:06:58 +02:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment fstab.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {struct fstab *} getfsspec (const char *@var{name})
|
|
|
|
This function returns the next entry of the @file{fstab} file which has
|
|
|
|
a string equal to @var{name} pointed to by the @code{fs_spec} element.
|
|
|
|
Since there is normally exactly one entry for each special device it
|
|
|
|
makes no sense to call this function more than once for the same
|
|
|
|
argument. If this is the first call to any of the functions handling
|
|
|
|
@file{fstab} since program start or the last call of @code{endfsent},
|
|
|
|
the file will be opened.
|
|
|
|
|
1999-08-27 21:06:58 +02:00
|
|
|
The function returns a pointer to a variable of type @code{struct
|
1998-06-11 23:06:58 +02:00
|
|
|
fstab}. This variable is shared by all threads and therefore this
|
|
|
|
function is not thread-safe. If an error occurred @code{getfsent}
|
1998-06-15 12:29:49 +02:00
|
|
|
returns a @code{NULL} pointer.
|
1998-06-11 23:06:58 +02:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment fstab.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {struct fstab *} getfsfile (const char *@var{name})
|
|
|
|
This function returns the next entry of the @file{fstab} file which has
|
|
|
|
a string equal to @var{name} pointed to by the @code{fs_file} element.
|
|
|
|
Since there is normally exactly one entry for each mount point it
|
|
|
|
makes no sense to call this function more than once for the same
|
|
|
|
argument. If this is the first call to any of the functions handling
|
|
|
|
@file{fstab} since program start or the last call of @code{endfsent},
|
|
|
|
the file will be opened.
|
|
|
|
|
1999-08-27 21:06:58 +02:00
|
|
|
The function returns a pointer to a variable of type @code{struct
|
1998-06-11 23:06:58 +02:00
|
|
|
fstab}. This variable is shared by all threads and therefore this
|
|
|
|
function is not thread-safe. If an error occurred @code{getfsent}
|
1998-06-15 12:29:49 +02:00
|
|
|
returns a @code{NULL} pointer.
|
1998-06-11 23:06:58 +02:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
|
2000-04-18 08:24:03 +02:00
|
|
|
@node mtab
|
2001-02-09 18:02:23 +01:00
|
|
|
@subsubsection The @file{mtab} file
|
2000-04-18 08:24:03 +02:00
|
|
|
The following functions and data structure access the @file{mtab} file.
|
1998-06-11 23:06:58 +02:00
|
|
|
|
2000-04-18 08:24:03 +02:00
|
|
|
@comment mntent.h
|
1998-06-11 23:06:58 +02:00
|
|
|
@comment BSD
|
|
|
|
@deftp {Data Type} {struct mntent}
|
|
|
|
This structure is used with the @code{getmntent}, @code{getmntent_t},
|
|
|
|
@code{addmntent}, and @code{hasmntopt} functions.
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item char *mnt_fsname
|
|
|
|
This element contains a pointer to a string describing the name of the
|
|
|
|
special device from which the filesystem is mounted. It corresponds to
|
|
|
|
the @code{fs_spec} element in @code{struct fstab}.
|
|
|
|
|
|
|
|
@item char *mnt_dir
|
|
|
|
This element points to a string describing the mount point of the
|
|
|
|
filesystem. It corresponds to the @code{fs_file} element in
|
|
|
|
@code{struct fstab}.
|
|
|
|
|
|
|
|
@item char *mnt_type
|
|
|
|
@code{mnt_type} describes the filesystem type and is therefore
|
|
|
|
equivalent to @code{fs_vfstype} in @code{struct fstab}. @file{mntent.h}
|
1999-08-27 21:06:58 +02:00
|
|
|
defines a few symbolic names for some of the values this string can have.
|
|
|
|
But since the kernel can support arbitrary filesystems it does not
|
1998-06-11 23:06:58 +02:00
|
|
|
make much sense to give them symbolic names. If one knows the symbol
|
|
|
|
name one also knows the filesystem name. Nevertheless here follows the
|
1999-08-27 21:06:58 +02:00
|
|
|
list of the symbols provided in @file{mntent.h}.
|
1998-06-11 23:06:58 +02:00
|
|
|
|
|
|
|
@vtable @code
|
|
|
|
@item MNTTYPE_IGNORE
|
|
|
|
This symbol expands to @code{"ignore"}. The value is sometime used in
|
|
|
|
@file{fstab} files to make sure entries are not used without removing them.
|
|
|
|
@item MNTTYPE_NFS
|
|
|
|
Expands to @code{"nfs"}. Using this macro sometimes could make sense
|
|
|
|
since it names the default NFS implementation, in case both version 2
|
|
|
|
and 3 are supported.
|
|
|
|
@item MNTTYPE_SWAP
|
|
|
|
This symbol expands to @code{"swap"}. It names the special @file{fstab}
|
|
|
|
entry which names one of the possibly multiple swap partitions.
|
|
|
|
@end vtable
|
|
|
|
|
|
|
|
@item char *mnt_opts
|
|
|
|
The element contains a string describing the options used while mounting
|
|
|
|
the filesystem. As for the equivalent element @code{fs_mntops} of
|
|
|
|
@code{struct fstab} it is best to use the function @code{getsubopt}
|
|
|
|
(@pxref{Suboptions}) to access the parts of this string.
|
|
|
|
|
|
|
|
The @file{mntent.h} file defines a number of macros with string values
|
|
|
|
which correspond to some of the options understood by the kernel. There
|
1999-08-27 21:06:58 +02:00
|
|
|
might be many more options which are possible so it doesn't make much sense
|
1998-06-11 23:06:58 +02:00
|
|
|
to rely on these macros but to be consistent here is the list:
|
|
|
|
|
|
|
|
@vtable @code
|
|
|
|
@item MNTOPT_DEFAULTS
|
|
|
|
Expands to @code{"defaults"}. This option should be used alone since it
|
2000-02-22 10:00:35 +01:00
|
|
|
indicates all values for the customizable values are chosen to be the
|
1998-06-11 23:06:58 +02:00
|
|
|
default.
|
|
|
|
@item MNTOPT_RO
|
1998-06-15 20:12:05 +02:00
|
|
|
Expands to @code{"ro"}. See the @code{FSTAB_RO} value, it means the
|
1998-06-11 23:06:58 +02:00
|
|
|
filesystem is mounted read-only.
|
|
|
|
@item MNTOPT_RW
|
1998-06-15 20:12:05 +02:00
|
|
|
Expand to @code{"rw"}. See the @code{FSTAB_RW} value, it means the
|
1998-06-11 23:06:58 +02:00
|
|
|
filesystem is mounted with read and write permissions.
|
|
|
|
@item MNTOPT_SUID
|
|
|
|
Expands to @code{"suid"}. This means that the SUID bit (@pxref{How
|
|
|
|
Change Persona}) is respected when a program from the filesystem is
|
|
|
|
started.
|
|
|
|
@item MNTOPT_NOSUID
|
|
|
|
Expands to @code{"nosuid"}. This is the opposite of @code{MNTOPT_SUID},
|
1998-06-15 12:29:49 +02:00
|
|
|
the SUID bit for all files from the filesystem is ignored.
|
1998-06-11 23:06:58 +02:00
|
|
|
@item MNTOPT_NOAUTO
|
|
|
|
Expands to @code{"noauto"}. At startup time the @code{mount} program
|
|
|
|
will ignore this entry if it is started with the @code{-a} option to
|
|
|
|
mount all filesystems mentioned in the @file{fstab} file.
|
|
|
|
@end vtable
|
|
|
|
|
|
|
|
As for the @code{FSTAB_*} entries introduced above it is important to
|
|
|
|
use @code{strcmp} to check for equality.
|
|
|
|
|
|
|
|
@item mnt_freq
|
|
|
|
This elements corresponds to @code{fs_freq} and also specifies the
|
|
|
|
frequency in days in which dumps are made.
|
|
|
|
|
|
|
|
@item mnt_passno
|
|
|
|
This element is equivalent to @code{fs_passno} with the same meaning
|
|
|
|
which is uninteresting for all programs beside @code{dump}.
|
|
|
|
@end table
|
|
|
|
@end deftp
|
|
|
|
|
|
|
|
For accessing the @file{mtab} file there is again a set of three
|
|
|
|
functions to access all entries in a row. Unlike the functions to
|
|
|
|
handle @file{fstab} these functions do not access a fixed file and there
|
1998-06-15 12:29:49 +02:00
|
|
|
is even a thread safe variant of the get function. Beside this the GNU
|
|
|
|
libc contains functions to alter the file and test for specific options.
|
1998-06-11 23:06:58 +02:00
|
|
|
|
|
|
|
@comment mntent.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {FILE *} setmntent (const char *@var{file}, const char *@var{mode})
|
|
|
|
The @code{setmntent} function prepares the file named @var{FILE} which
|
|
|
|
must be in the format of a @file{fstab} and @file{mtab} file for the
|
|
|
|
upcoming processing through the other functions of the family. The
|
|
|
|
@var{mode} parameter can be chosen in the way the @var{opentype}
|
|
|
|
parameter for @code{fopen} (@pxref{Opening Streams}) can be chosen. If
|
|
|
|
the file is opened for writing the file is also allowed to be empty.
|
|
|
|
|
|
|
|
If the file was successfully opened @code{setmntent} returns a file
|
|
|
|
descriptor for future use. Otherwise the return value is @code{NULL}
|
|
|
|
and @code{errno} is set accordingly.
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment mntent.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int endmntent (FILE *@var{stream})
|
|
|
|
This function takes for the @var{stream} parameter a file handle which
|
|
|
|
previously was returned from the @code{setmntent} call.
|
|
|
|
@code{endmntent} closes the stream and frees all resources.
|
|
|
|
|
1998-06-15 12:29:49 +02:00
|
|
|
The return value is @math{1} unless an error occurred in which case it
|
|
|
|
is @math{0}.
|
1998-06-11 23:06:58 +02:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment mntent.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {struct mntent *} getmntent (FILE *@var{stream})
|
|
|
|
The @code{getmntent} function takes as the parameter a file handle
|
|
|
|
previously returned by successful call to @code{setmntent}. It returns
|
|
|
|
a pointer to a static variable of type @code{struct mntent} which is
|
|
|
|
filled with the information from the next entry from the file currently
|
|
|
|
read.
|
|
|
|
|
1999-07-26 04:38:26 +02:00
|
|
|
The file format used prescribes the use of spaces or tab characters to
|
2003-11-29 07:40:52 +01:00
|
|
|
separate the fields. This makes it harder to use name containing one
|
|
|
|
of these characters (e.g., mount points using spaces). Therefore
|
|
|
|
these characters are encoded in the files and the @code{getmntent}
|
|
|
|
function takes care of the decoding while reading the entries back in.
|
|
|
|
@code{'\040'} is used to encode a space character, @code{'\011'} to
|
|
|
|
encode a tab character, @code{'\012'} to encode a newline character,
|
|
|
|
and @code{'\\'} to encode a backslash.
|
1999-07-26 04:38:26 +02:00
|
|
|
|
1998-06-11 23:06:58 +02:00
|
|
|
If there was an error or the end of the file is reached the return value
|
|
|
|
is @code{NULL}.
|
|
|
|
|
|
|
|
This function is not thread-safe since all calls to this function return
|
|
|
|
a pointer to the same static variable. @code{getmntent_r} should be
|
1998-06-15 12:29:49 +02:00
|
|
|
used in situations where multiple threads access the file.
|
1998-06-11 23:06:58 +02:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment mntent.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {struct mntent *} getmntent_r (FILE *@var{stream}, struct mentent *@var{result}, char *@var{buffer}, int @var{bufsize})
|
|
|
|
The @code{getmntent_r} function is the reentrant variant of
|
|
|
|
@code{getmntent}. It also returns the next entry from the file and
|
|
|
|
returns a pointer. The actual variable the values are stored in is not
|
|
|
|
static, though. Instead the function stores the values in the variable
|
|
|
|
pointed to by the @var{result} parameter. Additional information (e.g.,
|
|
|
|
the strings pointed to by the elements of the result) are kept in the
|
|
|
|
buffer of size @var{bufsize} pointed to by @var{buffer}.
|
|
|
|
|
1999-07-26 04:38:26 +02:00
|
|
|
Escaped characters (space, tab, backslash) are converted back in the
|
|
|
|
same way as it happens for @code{getmentent}.
|
|
|
|
|
1998-06-15 12:29:49 +02:00
|
|
|
The function returns a @code{NULL} pointer in error cases. Errors could be:
|
1998-06-11 23:06:58 +02:00
|
|
|
@itemize @bullet
|
|
|
|
@item
|
|
|
|
error while reading the file,
|
|
|
|
@item
|
|
|
|
end of file reached,
|
|
|
|
@item
|
|
|
|
@var{bufsize} is too small for reading a complete new entry.
|
|
|
|
@end itemize
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment mntent.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int addmntent (FILE *@var{stream}, const struct mntent *@var{mnt})
|
1999-08-27 21:06:58 +02:00
|
|
|
The @code{addmntent} function allows adding a new entry to the file
|
1998-06-11 23:06:58 +02:00
|
|
|
previously opened with @code{setmntent}. The new entries are always
|
|
|
|
appended. I.e., even if the position of the file descriptor is not at
|
1998-06-15 12:29:49 +02:00
|
|
|
the end of the file this function does not overwrite an existing entry
|
1998-06-11 23:06:58 +02:00
|
|
|
following the current position.
|
|
|
|
|
|
|
|
The implication of this is that to remove an entry from a file one has
|
|
|
|
to create a new file while leaving out the entry to be removed and after
|
|
|
|
closing the file remove the old one and rename the new file to the
|
|
|
|
chosen name.
|
|
|
|
|
1999-07-26 04:38:26 +02:00
|
|
|
This function takes care of spaces and tab characters in the names to be
|
|
|
|
written to the file. It converts them and the backslash character into
|
|
|
|
the format describe in the @code{getmntent} description above.
|
|
|
|
|
1998-06-15 12:29:49 +02:00
|
|
|
This function returns @math{0} in case the operation was successful.
|
|
|
|
Otherwise the return value is @math{1} and @code{errno} is set
|
1998-06-11 23:06:58 +02:00
|
|
|
appropriately.
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment mntent.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun {char *} hasmntopt (const struct mntent *@var{mnt}, const char *@var{opt})
|
|
|
|
This function can be used to check whether the string pointed to by the
|
|
|
|
@code{mnt_opts} element of the variable pointed to by @var{mnt} contains
|
|
|
|
the option @var{opt}. If this is true a pointer to the beginning of the
|
|
|
|
option in the @code{mnt_opts} element is returned. If no such option
|
1998-06-15 12:29:49 +02:00
|
|
|
exists the function returns @code{NULL}.
|
1998-06-11 23:06:58 +02:00
|
|
|
|
|
|
|
This function is useful to test whether a specific option is present but
|
|
|
|
when all options have to be processed one is better off with using the
|
|
|
|
@code{getsubopt} function to iterate over all options in the string.
|
|
|
|
@end deftypefun
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
@node Other Mount Information
|
2001-02-09 18:02:23 +01:00
|
|
|
@subsubsection Other (Non-libc) Sources of Mount Information
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
On a system with a Linux kernel and the @code{proc} filesystem, you can
|
|
|
|
get information on currently mounted filesystems from the file
|
|
|
|
@file{mounts} in the @code{proc} filesystem. Its format is similar to
|
|
|
|
that of the @file{mtab} file, but represents what is truly mounted
|
|
|
|
without relying on facilities outside the kernel to keep @file{mtab} up
|
|
|
|
to date.
|
|
|
|
|
|
|
|
|
2000-05-21 23:22:28 +02:00
|
|
|
@node Mount-Unmount-Remount, , Mount Information, Filesystem Handling
|
2001-02-09 18:02:23 +01:00
|
|
|
@subsection Mount, Unmount, Remount
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
This section describes the functions for mounting, unmounting, and
|
|
|
|
remounting filesystems.
|
|
|
|
|
|
|
|
Only the superuser can mount, unmount, or remount a filesystem.
|
|
|
|
|
|
|
|
These functions do not access the @file{fstab} and @file{mtab} files. You
|
|
|
|
should maintain and use these separately. @xref{Mount Information}.
|
|
|
|
|
|
|
|
The symbols in this section are declared in @file{sys/mount.h}.
|
|
|
|
|
|
|
|
@comment sys/mount.h
|
2000-04-18 08:48:18 +02:00
|
|
|
@comment SVID, BSD
|
2000-04-18 08:24:03 +02:00
|
|
|
@deftypefun {int} mount (const char *@var{special_file}, const char *@var{dir}, const char *@var{fstype}, unsigned long int @var{options}, const void *@var{data})
|
|
|
|
|
2000-04-18 08:48:18 +02:00
|
|
|
@code{mount} mounts or remounts a filesystem. The two operations are
|
2001-05-21 19:38:30 +02:00
|
|
|
quite different and are merged rather unnaturally into this one function.
|
2000-04-18 08:48:18 +02:00
|
|
|
The @code{MS_REMOUNT} option, explained below, determines whether
|
2000-04-18 08:24:03 +02:00
|
|
|
@code{mount} mounts or remounts.
|
|
|
|
|
|
|
|
For a mount, the filesystem on the block device represented by the
|
|
|
|
device special file named @var{special_file} gets mounted over the mount
|
|
|
|
point @var{dir}. This means that the directory @var{dir} (along with any
|
|
|
|
files in it) is no longer visible; in its place (and still with the name
|
|
|
|
@var{dir}) is the root directory of the filesystem on the device.
|
|
|
|
|
|
|
|
As an exception, if the filesystem type (see below) is one which is not
|
|
|
|
based on a device (e.g. ``proc''), @code{mount} instantiates a
|
|
|
|
filesystem and mounts it over @var{dir} and ignores @var{special_file}.
|
|
|
|
|
|
|
|
For a remount, @var{dir} specifies the mount point where the filesystem
|
|
|
|
to be remounted is (and remains) mounted and @var{special_file} is
|
|
|
|
ignored. Remounting a filesystem means changing the options that control
|
|
|
|
operations on the filesystem while it is mounted. It does not mean
|
|
|
|
unmounting and mounting again.
|
|
|
|
|
|
|
|
For a mount, you must identify the type of the filesystem as
|
|
|
|
@var{fstype}. This type tells the kernel how to access the filesystem
|
|
|
|
and can be thought of as the name of a filesystem driver. The
|
|
|
|
acceptable values are system dependent. On a system with a Linux kernel
|
|
|
|
and the @code{proc} filesystem, the list of possible values is in the
|
|
|
|
file @file{filesystems} in the @code{proc} filesystem (e.g. type
|
|
|
|
@kbd{cat /proc/filesystems} to see the list). With a Linux kernel, the
|
|
|
|
types of filesystems that @code{mount} can mount, and their type names,
|
|
|
|
depends on what filesystem drivers are configured into the kernel or
|
|
|
|
loaded as loadable kernel modules. An example of a common value for
|
|
|
|
@var{fstype} is @code{ext2}.
|
|
|
|
|
|
|
|
For a remount, @code{mount} ignores @var{fstype}.
|
|
|
|
|
|
|
|
@c This is traditionally called "rwflag" for historical reasons.
|
|
|
|
@c No point in confusing people today, though.
|
|
|
|
@var{options} specifies a variety of options that apply until the
|
2000-04-22 08:50:46 +02:00
|
|
|
filesystem is unmounted or remounted. The precise meaning of an option
|
2000-04-18 08:24:03 +02:00
|
|
|
depends on the filesystem and with some filesystems, an option may have
|
|
|
|
no effect at all. Furthermore, for some filesystems, some of these
|
|
|
|
options (but never @code{MS_RDONLY}) can be overridden for individual
|
|
|
|
file accesses via @code{ioctl}.
|
|
|
|
|
|
|
|
@var{options} is a bit string with bit fields defined using the
|
|
|
|
following mask and masked value macros:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item MS_MGC_MASK
|
|
|
|
This multibit field contains a magic number. If it does not have the value
|
|
|
|
@code{MS_MGC_VAL}, @code{mount} assumes all the following bits are zero and
|
|
|
|
the @var{data} argument is a null string, regardless of their actual values.
|
|
|
|
|
|
|
|
@item MS_REMOUNT
|
|
|
|
This bit on means to remount the filesystem. Off means to mount it.
|
|
|
|
@c There is a mask MS_RMT_MASK in mount.h that says only two of the options
|
2000-04-30 22:53:48 +02:00
|
|
|
@c can be reset by remount. But the Linux kernel has its own version of
|
2000-04-18 08:24:03 +02:00
|
|
|
@c MS_RMT_MASK that says they all can be reset. As far as I can tell,
|
|
|
|
@c libc just passes the arguments straight through to the kernel.
|
|
|
|
|
|
|
|
@item MS_RDONLY
|
|
|
|
This bit on specifies that no writing to the filesystem shall be allowed
|
2000-04-18 08:48:18 +02:00
|
|
|
while it is mounted. This cannot be overridden by @code{ioctl}. This
|
2000-04-18 08:24:03 +02:00
|
|
|
option is available on nearly all filesystems.
|
|
|
|
|
|
|
|
@item S_IMMUTABLE
|
|
|
|
This bit on specifies that no writing to the files in the filesystem
|
|
|
|
shall be allowed while it is mounted. This can be overridden for a
|
|
|
|
particular file access by a properly privileged call to @code{ioctl}.
|
|
|
|
This option is a relatively new invention and is not available on many
|
|
|
|
filesystems.
|
|
|
|
|
|
|
|
@item S_APPEND
|
|
|
|
This bit on specifies that the only file writing that shall be allowed
|
|
|
|
while the filesystem is mounted is appending. Some filesystems allow
|
|
|
|
this to be overridden for a particular process by a properly privileged
|
|
|
|
call to @code{ioctl}. This is a relatively new invention and is not
|
|
|
|
available on many filesystems.
|
|
|
|
|
|
|
|
@item MS_NOSUID
|
|
|
|
This bit on specifies that Setuid and Setgid permissions on files in the
|
|
|
|
filesystem shall be ignored while it is mounted.
|
|
|
|
|
|
|
|
@item MS_NOEXEC
|
|
|
|
This bit on specifies that no files in the filesystem shall be executed
|
|
|
|
while the filesystem is mounted.
|
|
|
|
|
|
|
|
@item MS_NODEV
|
2000-04-18 08:48:18 +02:00
|
|
|
This bit on specifies that no device special files in the filesystem
|
2000-04-18 08:24:03 +02:00
|
|
|
shall be accessible while the filesystem is mounted.
|
|
|
|
|
|
|
|
@item MS_SYNCHRONOUS
|
2000-04-18 08:48:18 +02:00
|
|
|
This bit on specifies that all writes to the filesystem while it is
|
[BZ #2510, BZ #2830, BZ #3137, BZ #3313, BZ #3426, BZ #3465, BZ #3480, BZ #3483, BZ #3493, BZ #3514, BZ #3515, BZ #3664, BZ #3673, BZ #3674]
2007-01-11 Jakub Jelinek <jakub@redhat.com>
* sysdeps/i386/soft-fp/sfp-machine.h: Remove.
* sysdeps/x86_64/soft-fp/sfp-machine.h: Likewise.
2007-01-10 Ulrich Drepper <drepper@redhat.com>
* io/fts.c: Make sure fts_cur is always valid after return from
fts_read.
Patch by Miloslav Trmac <mitr@redhat.com>.
2006-10-27 Richard Sandiford <richard@codesourcery.com>
* elf/elf.h (R_MIPS_GLOB_DAT): Define.
(R_MIPS_NUM): Bump by 1.
2007-01-03 Jakub Jelinek <jakub@redhat.com>
* posix/execvp.c: Include alloca.h.
(allocate_scripts_argv): Renamed to...
(scripts_argv): ... this. Don't allocate buffer here nor count
arguments.
(execvp): Use alloca if possible.
* posix/Makefile: Add rules to build and run tst-vfork3 test.
* posix/tst-vfork3.c: New test.
* stdlib/Makefile (tst-strtod3-ENV): Define.
2007-01-02 Ulrich Drepper <drepper@redhat.com>
* posix/getconf.c: Update copyright year.
* nss/getent.c: Likewise.
* iconv/iconvconfig.c: Likewise.
* iconv/iconv_prog.c: Likewise.
* elf/ldconfig.c: Likewise.
* catgets/gencat.c: Likewise.
* csu/version.c: Likewise.
* elf/ldd.bash.in: Likewise.
* elf/sprof.c (print_version): Likewise.
* locale/programs/locale.c: Likewise.
* locale/programs/localedef.c: Likewise.
* nscd/nscd.c (print_version): Likewise.
* debug/xtrace.sh: Likewise.
* malloc/memusage.sh: Likewise.
* malloc/mtrace.pl: Likewise.
* debug/catchsegv.sh: Likewise.
2006-12-24 Ulrich Drepper <drepper@redhat.com>
* malloc/malloc.c (sYSMALLOc): Remove some unnecessary alignment
attempts.
2006-12-23 Ulrich Drepper <drepper@redhat.com>
* posix/wordexp.c: Remove some unnecessary tests.
2006-12-20 SUGIOKA Toshinobu <sugioka@itonet.co.jp>
* sysdeps/unix/sysv/linux/sh/bits/shm.h: New file.
* nss/getXXbyYY_r.c: Include atomic.h.
(INTERNAL (REENTRANT_NAME)): Write startp after start_fct,
add atomic_write_barrier () in between.
2006-11-28 Jakub Jelinek <jakub@redhat.com>
* elf/dl-support.c: Include dl-procinfo.h.
* sysdeps/powerpc/dl-procinfo.h (PPC_PLATFORM_POWER4,
PPC_PLATFORM_PPC970, PPC_PLATFORM_POWER5, PPC_PLATFORM_POWER5_PLUS,
PPC_PLATFORM_POWER6, PPC_PLATFORM_CELL_BE, PPC_PLATFORM_POWER6X):
Define.
(_dl_string_platform): Use PPC_PLATFORM_* macros instead of
hardcoded constants.
* sysdeps/powerpc/dl-procinfo.c (_dl_powerpc_platform): Use
PPC_PLATFORM_* macros for array designators.
2006-11-11 Steven Munroe <sjmunroe@us.ibm.com>
* sysdeps/powerpc/dl-procinfo.c (_dl_powerpc_cap_flags): Add 3 new cap
names to the beginning.
(_dl_powerpc_platforms): Add "power6x".
* sysdeps/powerpc/dl-procinfo.h (_DL_HWCAP_FIRST): Decrease.
(HWCAP_IMPORTANT): Add PPC_FEATURE_HAS_DFP.
(_DL_PLATFORMS_COUNT): Increase.
(_dl_string_platform): Handle power6x case.
* sysdeps/powerpc/sysdep.h (PPC_FEATURE_PA6T, PPC_FEATURE_HAS_DFP,
PPC_FEATURE_POWER6_EXT): Define.
(PPC_FEATURE_POWER5, PPC_FEATURE_POWER5_PLUS): Correct Comment.
[-2^31 .. 2^31) range.
* sysdeps/unix/sysv/linux/bits/statvfs.h: Define ST_RELATIME.
* sysdeps/unix/sysv/linux/internal_statvfs.c (__statvfs_getflags):
Handle relatime mount option.
2006-12-13 Jakub Jelinek <jakub@redhat.com>
* sysdeps/unix/sysv/linux/powerpc/powerpc32/setcontext.S: Include
kernel-features.h.
2006-12-11 Ulrich Drepper <drepper@redhat.com>
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Parse thousand
separators also if no non-zero digits found.
* stdlib/Makefile (tests): Add tst-strtod3.
[BZ #3664]
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Fix test to recognize
empty parsed strings.
* stdlib/Makefile (tests): Add tst-strtod2.
* stdlib/tst-strtod2.c: New file.
[BZ #3673]
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Fix exp_limit
computation.
* stdlib/Makefile (tests): Add tst-atof2.
* stdlib/tst-atof2.c: New file.
[BZ #3674]
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Adjust exponent value
correctly if removing trailing zero of hex-float.
* stdlib/Makefile (tests): Add tst-atof1.
* stdlib/tst-atof1.c: New file.
* misc/mntent_r.c (__hasmntopt): Check p[optlen] even when p == rest.
Start searching for next comma at p rather than rest.
* misc/Makefile (tests): Add tst-mntent2.
* misc/tst-mntent2.c: New test.
2006-12-08 Ulrich Drepper <drepper@redhat.com>
* malloc/memusage.c: Handle realloc with new size of zero and
non-NULL pointer correctly.
(me): Really write first record twice.
(struct entry): Make format bi-arch safe.
(dest): Write out more realloc statistics.
* malloc/memusagestat.c (struct entry): Make format bi-arch safe.
2006-12-05 Jakub Jelinek <jakub@redhat.com>
* nis/nis_subr.c (nis_getnames): Revert last change.
2006-12-03 Kaz Kojima <kkojima@rr.iij4u.or.jp>
* sysdeps/unix/sysv/linux/sh/sys/io.h: Removed.
2006-11-30 H.J. Lu <hongjiu.lu@intel.com>
* sysdeps/i386/i686/memcmp.S: Use jump table as the base of
jump table entries.
2006-11-30 Jan Kratochvil <jan.kratochvil@redhat.com>
* sysdeps/unix/sysv/linux/i386/clone.S: Provide CFI for the outermost
`clone' function to ensure proper unwinding stop of gdb.
* sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise.
2006-12-01 Ulrich Drepper <drepper@redhat.com>
* nscd/nscd.init: Remove obsolete and commented-out -S option
handling.
2006-11-23 Jakub Jelinek <jakub@redhat.com>
[BZ #3514]
* manual/string.texi (strncmp): Fix pastos from wcscmp description.
[BZ #3515]
* manual/string.texi (strtok): Remove duplicate paragraph.
2006-12-01 Jan Kratochvil <jan.kratochvil@redhat.com>
* sysdeps/unix/sysv/linux/x86_64/sigaction.c: Fix compatibility with
libgcc not supporting `rflags' unwinding (register # >= 17).
2006-11-30 Jakub Jelinek <jakub@redhat.com>
* sunrpc/svc_run.c (svc_run): Set my_pollfd to new_pollfd if realloc
succeeded.
2006-11-29 Daniel Jacobowitz <dan@codesourcery.com>
Jakub Jelinek <jakub@redhat.com>
Jan Kratochvil <jan.kratochvil@redhat.com>
* sysdeps/unix/sysv/linux/x86_64/sigaction.c (restore_rt): Add correct
unwind information.
* sysdeps/unix/sysv/linux/x86_64/Makefile: Provide symbols for
'restore_rt' even in the 'signal' directory.
* sysdeps/unix/sysv/linux/x86_64/ucontext_i.sym: Extend the regs list.
malloc crashed. Don't allocate memory unnecessarily in each
loop.
2006-10-21 Jakub Jelinek <jakub@redhat.com>
* resolv/mapv4v6addr.h (map_v4v6_address): Fix last change.
2006-11-20 Ulrich Drepper <drepper@redhat.com>
* resolv/mapv4v6addr.h (map_v4v6_address): Optimize a bit.
2006-11-18 Bruno Haible <bruno@clisp.org>
* sysdeps/unix/sysv/linux/i386/getgroups.c (__getgroups): Invoke
__sysconf only after having tried to call getgroups32.
2006-11-19 Ulrich Drepper <drepper@redhat.com>
* nss/nss_files/files-hosts.c (LINE_PARSER): Support IPv6-style
addresses for IPv4 queries if they can be mapped.
2006-11-16 Jakub Jelinek <jakub@redhat.com>
* sysdeps/x86_64/fpu/s_copysignf.S (__copysignf): Switch to .text.
* sysdeps/x86_64/fpu/s_copysign.S (__copysign): Likewise.
(signmask): Add .size directive.
(othermask): Add .type directive.
2006-11-14 Ulrich Drepper <drepper@redhat.com>
* po/nl.po: Update from translation team.
* timezone/zdump.c: Redo fix for BZ #3137.
2006-11-14 Jakub Jelinek <jakub@redhat.com>
* nss/nss_files/files-alias.c (get_next_alias): Set line back
to first_unused after parsing :include: file.
* timezone/africa: Update from tzdata2006o.
* timezone/antarctica: Likewise.
* timezone/asia: Likewise.
* timezone/australasia: Likewise.
* timezone/backward: Likewise.
* timezone/europe: Likewise.
* timezone/iso3166.tab: Likewise.
* timezone/northamerica: Likewise.
* timezone/southamerica: Likewise.
* timezone/zone.tab: Likewise.
* time/tzfile.c (__tzfile_read): Extend to handle new file format
on machines with 64-bit time_t.
* timezone/checktab.awk: Update from tzcode2006o.
* timezone/ialloc.c: Likewise.
* timezone/private.h: Likewise.
* timezone/scheck.c: Likewise.
* timezone/tzfile.h: Likewise.
* timezone/tzselect.ksh: Likewise.
* timezone/zdump.c: Likewise.
* timezone/zic.c: Likewise.
[BZ #3483]
* elf/ldconfig.c (main): Call setlocale and textdomain.
Patch mostly by Benno Schulenberg <bensberg@justemail.net>.
[BZ #3480]
* manual/argp.texi: Fix typos.
* manual/charset.texi: Likewise.
* manual/errno.texi: Likewise.
* manual/filesys.texi: Likewise.
* manual/lang.texi: Likewise.
* manual/maint.texi: Likewise.
* manual/memory.texi: Likewise.
* manual/message.texi: Likewise.
* manual/resource.texi: Likewise.
* manual/search.texi: Likewise.
* manual/signal.texi: Likewise.
* manual/startup.texi: Likewise.
* manual/stdio.texi: Likewise.
* manual/sysinfo.texi: Likewise.
* manual/syslog.texi: Likewise.
* manual/time.texi: Likewise.
Patch by Ralf Wildenhues <Ralf.Wildenhues@gmx.de>.
[BZ #3465]
* sunrpc/clnt_raw.c: Minimal message improvements.
* sunrpc/pm_getmaps.c: Likewise.
* nis/nss_nisplus/nisplus-publickey.c: Likewise.
* nis/nis_print_group_entry.c: Likewise.
* locale/programs/repertoire.c: Likewise.
* locale/programs/charmap.c: Likewise.
* malloc/memusage.sh: Likewise.
* elf/dl-deps.c: Likewise.
* locale/programs/ld-collate.c: Likewise.
* libio/vswprintf.c: Likewise.
* malloc/memusagestat.c: Likewise.
* sunrpc/auth_unix.c: Likewise.
* sunrpc/rpc_main.c: Likewise.
* nscd/cache.c: Likewise.
* locale/programs/repertoire.c: Unify output messages.
* locale/programs/charmap.c: Likewise.
* locale/programs/ld-ctype.c: Likewise.
* locale/programs/ld-monetary.c: Likewise.
* locale/programs/ld-numeric.c: Likewise.
* locale/programs/ld-time.c: Likewise.
* elf/ldconfig.c: Likewise.
* nscd/selinux.c: Likewise.
* elf/cache.c: Likewise.
Patch mostly by Benno Schulenberg <bensberg@justemail.net>.
2006-11-10 Jakub Jelinek <jakub@redhat.com>
* string/strxfrm_l.c (STRXFRM): Fix trailing \1 optimization
if N is one bigger than return value.
* string/tst-strxfrm2.c (do_test): Also test strxfrm with l1 + 1
and l1 last arguments, if buf is defined, verify the return value
equals to strlen (buf) and verify no byte beyond passed length
is modified.
2006-11-10 Ulrich Drepper <drepper@redhat.com>
* po/sv.po: Update from translation team.
* sysdeps/gnu/siglist.c (__old_sys_siglist, __old_sys_sigabbrev):
Use __new_sys_siglist instead of _sys_siglist_internal as
second macro argument.
(_old_sys_siglist): Use declare_symbol_alias macro instead of
strong_alias.
2006-11-09 Ulrich Drepper <drepper@redhat.com>
[BZ #3493]
* posix/unistd.h (sysconf): Remove const attribute.
* sysdeps/posix/getaddrinfo.c (getaddrinfo): Fix test for
temporary or deprecated addresses.
Patch by Sridhar Samudrala <sri@us.ibm.com>.
* string/Makefile (tests): Add tst-strxfrm2.
* string/tst-strxfrm2.c: New file.
2006-10-09 Jakub Jelinek <jakub@redhat.com>
* elf/dl-debug.c (_dl_debug_initialize): Check r->r_map for 0
rather than r->r_brk.
* string/strxfrm_l.c (STRXFRM): Do the trailing \1 removal
optimization even if needed > n.
2006-11-07 Jakub Jelinek <jakub@redhat.com>
* include/libc-symbols.h (declare_symbol): Rename to...
(declare_symbol_alias): ... this. Add ORIGINAL argument, imply
strong_alias (ORIGINAL, SYMBOL) in asm to make sure it preceedes
.size directive.
* sysdeps/gnu/errlist-compat.awk: Adjust for declare_symbol_alias
changes.
* sysdeps/gnu/siglist.c: Likewise.
2006-11-03 Steven Munroe <sjmunroe@us.ibm.com>
* sysdeps/powerpc/fpu/bits/mathinline.h
[__LIBC_INTERNAL_MATH_INLINES]: Moved to ...
* sysdeps/powerpc/fpu/math_private.h: ...here. New file.
2006-11-05 Ulrich Drepper <drepper@redhat.com>
* sysdeps/unix/sysv/linux/i386/sysconf.c (intel_check_word):
Update handling of cache descriptor 0x49 for new models.
* sysdeps/unix/sysv/linux/x86_64/sysconf.c (intel_check_word):
Likewise.
2006-11-02 Ulrich Drepper <drepper@redhat.com>
* configure.in: Work around ld --help change and avoid -z relro
test completely if the architecture doesn't care about security.
2006-11-01 Ulrich Drepper <drepper@redhat.com>
* po/sv.po: Update from translation team.
2006-10-31 Ulrich Drepper <drepper@redhat.com>
* stdlib/atexit.c (atexit): Don't mark as hidden when used to
generate compatibility version.
2006-10-29 Ulrich Drepper <drepper@redhat.com>
* configure.in: Relax -z relro requirement a bit.
* po/sv.po: Update from translation team.
2006-10-29 Jakub Jelinek <jakub@redhat.com>
* elf/dl-sym.c (do_sym): Use RTLD_SINGLE_THREAD_P.
* elf/dl-runtime.c (_dl_fixup, _dl_profile_fixup): Likewise.
* elf/dl-close.c (_dl_close_worker): Likewise.
* elf/dl-open.c (_dl_open_worker): Likewise.
* sysdeps/generic/sysdep-cancel.h (RTLD_SINGLE_THREAD_P): Define.
* configure.in: Require assembler support for visibility, compiler
support for visibility and aliases, linker support for various -z
options.
* Makeconfig: Remove conditional code which now is unnecessary.
* config.h.in: Likewise.
* config.make.in: Likewise.
* dlfcn/Makefile: Likewise.
* elf/Makefile: Likewise.
* elf/dl-load.c: Likewise.
* elf/rtld.c: Likewise.
* include/libc-symbols.h: Likewise.
* include/stdio.h: Likewise.
* io/Makefile: Likewise.
* io/fstat.c: Likewise.
* io/fstat64.c: Likewise.
* io/fstatat.c: Likewise.
* io/fstatat64.c: Likewise.
* io/lstat.c: Likewise.
* io/lstat64.c: Likewise.
* io/mknod.c: Likewise.
* io/mknodat.c: Likewise.
* io/stat.c: Likewise.
* io/stat64.c: Likewise.
* libio/stdio.c: Likewise.
* nscd/Makefile: Likewise.
* stdlib/Makefile: Likewise.
* stdlib/atexit.c: Likewise.
* sysdeps/generic/ldsodefs.h: Likewise.
* sysdeps/i386/dl-machine.h: Likewise.
* sysdeps/i386/sysdep.h: Likewise.
* sysdeps/i386/i686/memcmp.S: Likewise.
* sysdeps/powerpc/powerpc32/sysdep.h: Likewise.
* sysdeps/unix/sysv/linux/i386/sigaction.c: Likewise.
* sysdeps/unix/sysv/linux/x86_64/sigaction.c: Likewise.
* Makerules: USE_TLS support is now default.
* tls.make.c: Likewise.
* csu/Versions: Likewise.
* csu/libc-start.c: Likewise.
* csu/libc-tls.c: Likewise.
* csu/version.c: Likewise.
* dlfcn/dlinfo.c: Likewise.
* elf/dl-addr.c: Likewise.
* elf/dl-cache.c: Likewise.
* elf/dl-close.c: Likewise.
* elf/dl-iteratephdr.c: Likewise.
* elf/dl-load.c: Likewise.
* elf/dl-lookup.c: Likewise.
* elf/dl-object.c: Likewise.
* elf/dl-open.c: Likewise.
* elf/dl-reloc.c: Likewise.
* elf/dl-support.c: Likewise.
* elf/dl-sym.c: Likewise.
* elf/dl-sysdep.c: Likewise.
* elf/dl-tls.c: Likewise.
* elf/ldconfig.c: Likewise.
* elf/rtld.c: Likewise.
* elf/tst-tls-dlinfo.c: Likewise.
* elf/tst-tls1.c: Likewise.
* elf/tst-tls10.h: Likewise.
* elf/tst-tls14.c: Likewise.
* elf/tst-tls2.c: Likewise.
* elf/tst-tls3.c: Likewise.
* elf/tst-tls4.c: Likewise.
* elf/tst-tls5.c: Likewise.
* elf/tst-tls6.c: Likewise.
* elf/tst-tls7.c: Likewise.
* elf/tst-tls8.c: Likewise.
* elf/tst-tls9.c: Likewise.
* elf/tst-tlsmod1.c: Likewise.
* elf/tst-tlsmod13.c: Likewise.
* elf/tst-tlsmod13a.c: Likewise.
* elf/tst-tlsmod14a.c: Likewise.
* elf/tst-tlsmod2.c: Likewise.
* elf/tst-tlsmod3.c: Likewise.
* elf/tst-tlsmod4.c: Likewise.
* elf/tst-tlsmod5.c: Likewise.
* elf/tst-tlsmod6.c: Likewise.
* include/errno.h: Likewise.
* include/link.h: Likewise.
* include/tls.h: Likewise.
* locale/global-locale.c: Likewise.
* locale/localeinfo.h: Likewise.
* malloc/arena.c: Likewise.
* malloc/hooks.c: Likewise.
* malloc/malloc.c: Likewise.
* resolv/Versions: Likewise.
* sysdeps/alpha/dl-machine.h: Likewise.
* sysdeps/alpha/libc-tls.c: Likewise.
* sysdeps/generic/ldsodefs.h: Likewise.
* sysdeps/generic/tls.h: Likewise.
* sysdeps/i386/dl-machine.h: Likewise.
* sysdeps/ia64/dl-machine.h: Likewise.
* sysdeps/ia64/libc-tls.c: Likewise.
* sysdeps/mach/hurd/fork.c: Likewise.
* sysdeps/mach/hurd/i386/tls.h: Likewise.
* sysdeps/powerpc/powerpc32/dl-machine.c: Likwise.
* sysdeps/powerpc/powerpc32/dl-machine.h: Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.h: Likewise.
* sysdeps/s390/libc-tls.c: Likewise.
* sysdeps/s390/s390-32/dl-machine.h: Likewise.
* sysdeps/s390/s390-64/dl-machine.h: Likewise.
* sysdeps/sh/dl-machine.h: Likewise.
* sysdeps/sparc/sparc32/dl-machine.h: Likewise.
* sysdeps/sparc/sparc64/dl-machine.h: Likewise.
* sysdeps/x86_64/dl-machine.h: Likewise.
[BZ #3426]
* stdlib/stdlib.h: Adjust comment for canonicalize_file_name to
reality.
2006-10-27 Jakub Jelinek <jakub@redhat.com>
* elf/dl-lookup.c (_dl_debug_bindings): Remove unused symbol_scope
argument.
(_dl_lookup_symbol_x): Adjust caller.
* sysdeps/generic/ldsodefs.h (struct link_namespaces): Remove
_ns_global_scope.
* elf/rtld.c (dl_main): Don't initialize _ns_global_scope.
* elf/dl-libc.c: Revert l_scope name changes.
* elf/dl-load.c: Likewise.
* elf/dl-object.c: Likewise.
* elf/rtld.c: Likewise.
* elf/dl-close.c (_dl_close): Likewise.
* elf/dl-open.c (dl_open_worker): Likewise. If not SINGLE_THREAD_P,
always use __rtld_mrlock_{change,done}. Always free old scope list
here if not l_scope_mem.
* elf/dl-runtime.c (_dl_fixup, _dl_profile_fixup): Revert l_scope name
change. Never free scope list here. Just __rtld_mrlock_lock before
the lookup and __rtld_mrlock_unlock it after the lookup.
* elf/dl-sym.c: Likewise.
* include/link.h (struct r_scoperec): Remove.
(struct link_map): Replace l_scoperec with l_scope, l_scoperec_mem
with l_scope_mem and l_scoperec_lock with l_scope_lock.
2006-10-25 Ulrich Drepper <drepper@redhat.com>
* sysdeps/gnu/netinet/tcp.h: Define TCP_CONGESTION.
2006-10-18 Ulrich Drepper <drepper@redhat.com>
* configure.in: Disable building profile libraries by default.
2006-10-18 Ulrich Drepper <drepper@redhat.com>
* elf/dl-lookup.c (_dl_lookup_symbol_x): Add warning to
_dl_lookup_symbol_x code.
2006-10-17 Jakub Jelinek <jakub@redhat.com>
* elf/dl-runtime.c: Include sysdep-cancel.h.
(_dl_fixup, _dl_profile_fixup): Use __rtld_mrlock_* and
scoperec->nusers only if !SINGLE_THREAD_P. Use atomic_*
instead of catomic_* macros.
* elf/dl-sym.c: Include sysdep-cancel.h.
(do_sym): Use __rtld_mrlock_* and scoperec->nusers only
if !SINGLE_THREAD_P. Use atomic_* instead of catomic_* macros.
* elf/dl-close.c: Include sysdep-cancel.h.
(_dl_close): Use __rtld_mrlock_* and scoperec->nusers only
if !SINGLE_THREAD_P. Use atomic_* instead of catomic_* macros.
* elf/dl-open.c: Include sysdep-cancel.h.
(dl_open_worker): Use __rtld_mrlock_* and scoperec->nusers only
if !SINGLE_THREAD_P. Use atomic_* instead of catomic_* macros.
2006-10-17 Jakub Jelinek <jakub@redhat.com>
[BZ #3313]
* malloc/malloc.c (malloc_consolidate): Set maxfb to address of last
fastbin rather than end of fastbin array.
2006-10-18 Ulrich Drepper <drepper@redhat.com>
* sysdeps/i386/i486/bits/atomic.h (catomic_decrement): Use correct
body macro.
* sysdeps/x86_64/bits/atomic.h
(__arch_c_compare_and_exchange_val_64_acq): Add missing casts.
(catomic_decrement): Use correct body macro.
2006-10-17 Jakub Jelinek <jakub@redhat.com>
* include/atomic.h: Add a unique prefix to all local variables
in macros.
* csu/tst-atomic.c (do_test): Test also catomic_* macros.
2006-10-14 Ulrich Drepper <drepper@redhat.com>
* resolv/arpa/nameser.h: Document that ns_t_a6 is deprecated.
[BZ #3313]
* malloc/malloc.c (malloc_consolidate): Don't use get_fast_max to
determine highest fast bin to consolidate, always look into all of
them.
(do_check_malloc_state): Only require for empty bins for large
sizes in main arena.
* libio/stdio.h: Add more __wur attributes.
2006-11-12 Andreas Jaeger <aj@suse.de>
[BZ #2510]
* manual/search.texi (Hash Search Function): Clarify.
(Array Search Function): Clarify.
2006-11-12 Joseph Myers <joseph@codesourcery.com>
[BZ #2830]
* math/atest-exp.c (main): Cast hex value to mp_limb_t before
shifting.
* math/atest-exp2.c (read_mpn_hex): Likewise.
* math/atest-sincos.c (main): Likewise.
* sysdeps/unix/sysv/linux/syscalls.list: Add epoll_pwait.
* sysdeps/unix/sysv/linux/sys/epoll.h: Declare epoll_pwait.
* sysdeps/unix/sysv/linux/Versions (libc): Add epoll_pwait for
version GLIBC_2.6.
* Versions.def: Add GLIBC_2.6 for libc.
* sysdeps/i386/i486/bits/atomic.h: Add catomic_* support.
2006-10-11 Jakub Jelinek <jakub@redhat.com>
* malloc/malloc.c (_int_malloc): Remove unused any_larger variable.
* nis/nis_defaults.c (__nis_default_access): Don't call getenv twice.
* nis/nis_subr.c (nis_getnames): Use __secure_getenv instead of getenv.
* sysdeps/generic/unsecvars.h: Add NIS_PATH.
2006-10-11 Ulrich Drepper <drepper@redhat.com>
* include/atomic.c: Define catomic_* operations.
* sysdeps/x86_64/bits/atomic.h: Likewise. Fix a few minor problems.
* stdlib/cxa_finalize.c: Use catomic_* operations instead of atomic_*.
* malloc/memusage.c: Likewise.
* gmon/mcount.c: Likewise.
* elf/dl-close.c: Likewise.
* elf/dl-open.c: Likewise.
* elf/dl-profile.c: Likewise.
* elf/dl-sym.c: Likewise.
* elf/dl-runtime.c: Likewise.
* elf/dl-fptr.c: Likewise.
* resolv/res_libc.c: Likewise.
2006-10-10 Roland McGrath <roland@frob.com>
* sysdeps/mach/hurd/utimes.c: Use a union to avoid an improper cast.
* sysdeps/mach/hurd/futimes.c: Likewise.
* sysdeps/mach/hurd/lutimes.c: Likewise.
2006-10-09 Ulrich Drepper <drepper@redhat.com>
Jakub Jelinek <jakub@redhat.com>
Implement reference counting of scope records.
* elf/dl-close.c (_dl_close): Remove all scopes from removed objects
from the list in objects which remain. Always allocate new scope
record.
* elf/dl-open.c (dl_open_worker): When growing array for scopes,
don't resize, allocate a new one.
* elf/dl-runtime.c: Update reference counters before using a scope
array.
* elf/dl-sym.c: Likewise.
* elf/dl-libc.c: Adjust for l_scope name change.
* elf/dl-load.c: Likewise.
* elf/dl-object.c: Likewise.
* elf/rtld.c: Likewise.
* include/link.h: Include <rtld-lowlevel.h>. Define struct
r_scoperec. Replace r_scope with pointer to r_scoperec structure.
Add l_scoperec_lock.
* sysdeps/generic/ldsodefs.h: Include <rtld-lowlevel.h>.
* sysdeps/generic/rtld-lowlevel.h: New file.
* include/atomic.h: Rename atomic_and to atomic_and_val and
atomic_or to atomic_or_val. Define new macros atomic_and and
atomic_or which do not return values.
* sysdeps/x86_64/bits/atomic.h: Define atomic_and and atomic_or.
Various cleanups.
* sysdeps/i386/i486/bits/atomic.h: Likewise.
* po/sv.po: Update from translation team.
2006-10-07 Ulrich Drepper <drepper@redhat.com>
* Versions.def: Add GLIBC_2.6 to libpthread.
* include/shlib-compat.h (SHLIB_COMPAT): Expand parameters before use.
(versioned_symbol): Likewise.
(compat_symbol): Likewise.
* po/tr.po: Update from translation team.
* nis/Banner: Removed. It's been integral part forever and the
author info is incomplete anyway.
* libio/Banner: Likewise.
2006-10-06 Ulrich Drepper <drepper@redhat.com>
* version.h (VERSION): Bump to 2.5.90 for new development tree.
2007-01-11 22:51:07 +01:00
|
|
|
mounted shall be synchronous; i.e., data shall be synced before each
|
2000-04-18 08:24:03 +02:00
|
|
|
write completes rather than held in the buffer cache.
|
|
|
|
|
|
|
|
@item MS_MANDLOCK
|
|
|
|
This bit on specifies that mandatory locks on files shall be permitted while
|
|
|
|
the filesystem is mounted.
|
|
|
|
|
|
|
|
@item MS_NOATIME
|
|
|
|
This bit on specifies that access times of files shall not be updated when
|
|
|
|
the files are accessed while the filesystem is mounted.
|
|
|
|
|
|
|
|
@item MS_NODIRATIME
|
|
|
|
This bit on specifies that access times of directories shall not be updated
|
|
|
|
when the directories are accessed while the filesystem in mounted.
|
|
|
|
|
|
|
|
@c there is also S_QUOTA Linux fs.h (mount.h still uses its former name
|
|
|
|
@c S_WRITE), but I can't see what it does. Turns on quotas, I guess.
|
|
|
|
|
|
|
|
@end table
|
|
|
|
|
|
|
|
Any bits not covered by the above masks should be set off; otherwise,
|
|
|
|
results are undefined.
|
|
|
|
|
|
|
|
The meaning of @var{data} depends on the filesystem type and is controlled
|
|
|
|
entirely by the filesystem driver in the kernel.
|
|
|
|
|
|
|
|
Example:
|
|
|
|
|
|
|
|
@smallexample
|
|
|
|
@group
|
|
|
|
#include <sys/mount.h>
|
|
|
|
|
|
|
|
mount("/dev/hdb", "/cdrom", MS_MGC_VAL | MS_RDONLY | MS_NOSUID, "");
|
|
|
|
|
|
|
|
mount("/dev/hda2", "/mnt", MS_MGC_VAL | MS_REMOUNT, "");
|
|
|
|
|
|
|
|
@end group
|
|
|
|
@end smallexample
|
|
|
|
|
|
|
|
Appropriate arguments for @code{mount} are conventionally recorded in
|
|
|
|
the @file{fstab} table. @xref{Mount Information}.
|
|
|
|
|
|
|
|
The return value is zero if the mount or remount is successful. Otherwise,
|
2000-04-18 08:48:18 +02:00
|
|
|
it is @code{-1} and @code{errno} is set appropriately. The values of
|
2000-04-18 08:24:03 +02:00
|
|
|
@code{errno} are filesystem dependent, but here is a general list:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item EPERM
|
|
|
|
The process is not superuser.
|
|
|
|
@item ENODEV
|
|
|
|
The file system type @var{fstype} is not known to the kernel.
|
|
|
|
@item ENOTBLK
|
|
|
|
The file @var{dev} is not a block device special file.
|
|
|
|
@item EBUSY
|
|
|
|
|
2000-06-02 02:27:08 +02:00
|
|
|
@itemize @bullet
|
2000-04-18 08:24:03 +02:00
|
|
|
|
2000-04-18 08:48:18 +02:00
|
|
|
@item
|
2000-04-18 08:24:03 +02:00
|
|
|
The device is already mounted.
|
|
|
|
|
|
|
|
@item
|
|
|
|
The mount point is busy. (E.g. it is some process' working directory or
|
|
|
|
has a filesystem mounted on it already).
|
|
|
|
|
|
|
|
@item
|
|
|
|
The request is to remount read-only, but there are files open for write.
|
|
|
|
@end itemize
|
|
|
|
|
|
|
|
@item EINVAL
|
2000-06-02 02:27:08 +02:00
|
|
|
@itemize @bullet
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
@item
|
|
|
|
A remount was attempted, but there is no filesystem mounted over the
|
|
|
|
specified mount point.
|
|
|
|
|
2000-04-18 08:48:18 +02:00
|
|
|
@item
|
2000-04-18 08:24:03 +02:00
|
|
|
The supposed filesystem has an invalid superblock.
|
|
|
|
|
|
|
|
@end itemize
|
|
|
|
|
2001-05-21 19:38:30 +02:00
|
|
|
@item EACCES
|
2000-06-02 02:27:08 +02:00
|
|
|
@itemize @bullet
|
2000-04-18 08:24:03 +02:00
|
|
|
|
|
|
|
@item
|
2000-04-18 08:48:18 +02:00
|
|
|
The filesystem is inherently read-only (possibly due to a switch on the
|
2000-04-18 08:24:03 +02:00
|
|
|
device) and the process attempted to mount it read/write (by setting the
|
|
|
|
@code{MS_RDONLY} bit off).
|
|
|
|
|
|
|
|
@item
|
|
|
|
@var{special_file} or @var{dir} is not accessible due to file permissions.
|
|
|
|
|
|
|
|
@item
|
|
|
|
@var{special_file} is not accessible because it is in a filesystem that is
|
|
|
|
mounted with the @code{MS_NODEV} option.
|
|
|
|
|
|
|
|
@end itemize
|
|
|
|
|
|
|
|
@item EM_FILE
|
|
|
|
The table of dummy devices is full. @code{mount} needs to create a
|
|
|
|
dummy device (aka ``unnamed'' device) if the filesystem being mounted is
|
|
|
|
not one that uses a device.
|
|
|
|
|
|
|
|
@end table
|
|
|
|
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
|
|
|
|
@comment sys/mount.h
|
2000-04-18 08:48:18 +02:00
|
|
|
@comment GNU
|
2000-04-18 08:24:03 +02:00
|
|
|
@deftypefun {int} umount2 (const char *@var{file}, int @var{flags})
|
|
|
|
|
|
|
|
@code{umount2} unmounts a filesystem.
|
|
|
|
|
|
|
|
You can identify the filesystem to unmount either by the device special
|
|
|
|
file that contains the filesystem or by the mount point. The effect is
|
|
|
|
the same. Specify either as the string @var{file}.
|
|
|
|
|
2000-04-18 08:48:18 +02:00
|
|
|
@var{flags} contains the one-bit field identified by the following
|
2000-04-18 08:24:03 +02:00
|
|
|
mask macro:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
|
|
|
|
@item MNT_FORCE
|
|
|
|
This bit on means to force the unmounting even if the filesystem is
|
|
|
|
busy, by making it unbusy first. If the bit is off and the filesystem is
|
|
|
|
busy, @code{umount2} fails with @code{errno} = @code{EBUSY}. Depending
|
|
|
|
on the filesystem, this may override all, some, or no busy conditions.
|
|
|
|
|
|
|
|
@end table
|
|
|
|
|
|
|
|
All other bits in @var{flags} should be set to zero; otherwise, the result
|
|
|
|
is undefined.
|
|
|
|
|
|
|
|
Example:
|
|
|
|
|
|
|
|
@smallexample
|
|
|
|
@group
|
|
|
|
#include <sys/mount.h>
|
|
|
|
|
|
|
|
umount2("/mnt", MNT_FORCE);
|
|
|
|
|
|
|
|
umount2("/dev/hdd1", 0);
|
|
|
|
|
|
|
|
@end group
|
|
|
|
@end smallexample
|
|
|
|
|
|
|
|
After the filesystem is unmounted, the directory that was the mount point
|
|
|
|
is visible, as are any files in it.
|
|
|
|
|
|
|
|
As part of unmounting, @code{umount2} syncs the filesystem.
|
|
|
|
|
|
|
|
If the unmounting is successful, the return value is zero. Otherwise, it
|
|
|
|
is @code{-1} and @code{errno} is set accordingly:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item EPERM
|
|
|
|
The process is not superuser.
|
|
|
|
@item EBUSY
|
|
|
|
The filesystem cannot be unmounted because it is busy. E.g. it contains
|
|
|
|
a directory that is some process's working directory or a file that some
|
|
|
|
process has open. With some filesystems in some cases, you can avoid
|
|
|
|
this failure with the @code{MNT_FORCE} option.
|
|
|
|
|
|
|
|
@item EINVAL
|
2000-04-18 08:48:18 +02:00
|
|
|
@var{file} validly refers to a file, but that file is neither a mount
|
2000-04-18 08:24:03 +02:00
|
|
|
point nor a device special file of a currently mounted filesystem.
|
|
|
|
|
|
|
|
@end table
|
2000-04-18 08:48:18 +02:00
|
|
|
|
|
|
|
This function is not available on all systems.
|
2000-04-18 08:24:03 +02:00
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
@comment sys/mount.h
|
2000-04-18 08:48:18 +02:00
|
|
|
@comment SVID, GNU
|
2000-04-18 08:24:03 +02:00
|
|
|
@deftypefun {int} umount (const char *@var{file})
|
|
|
|
|
2000-04-18 08:48:18 +02:00
|
|
|
@code{umount} does the same thing as @code{umount2} with @var{flags} set
|
|
|
|
to zeroes. It is more widely available than @code{umount2} but since it
|
|
|
|
lacks the possibility to forcefully unmount a filesystem is deprecated
|
|
|
|
when @code{umount2} is also available.
|
2000-04-18 08:24:03 +02:00
|
|
|
@end deftypefun
|
2000-04-30 22:53:48 +02:00
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
@node System Parameters
|
|
|
|
@section System Parameters
|
|
|
|
|
|
|
|
This section describes the @code{sysctl} function, which gets and sets
|
|
|
|
a variety of system parameters.
|
|
|
|
|
|
|
|
The symbols used in this section are declared in the file @file{sysctl.h}.
|
|
|
|
|
|
|
|
@comment sysctl.h
|
|
|
|
@comment BSD
|
|
|
|
@deftypefun int sysctl (int *@var{names}, int @var{nlen}, void *@var{oldval},
|
|
|
|
size_t *@var{oldlenp}, void *@var{newval}, size_t @var{newlen})
|
|
|
|
|
|
|
|
@code{sysctl} gets or sets a specified system parameter. There are so
|
|
|
|
many of these parameters that it is not practical to list them all here,
|
|
|
|
but here are some examples:
|
|
|
|
|
|
|
|
@itemize @bullet
|
|
|
|
@item network domain name
|
|
|
|
@item paging parameters
|
|
|
|
@item network Address Resolution Protocol timeout time
|
|
|
|
@item maximum number of files that may be open
|
|
|
|
@item root filesystem device
|
|
|
|
@item when kernel was built
|
|
|
|
@end itemize
|
|
|
|
|
|
|
|
The set of available parameters depends on the kernel configuration and
|
|
|
|
can change while the system is running, particularly when you load and
|
|
|
|
unload loadable kernel modules.
|
|
|
|
|
|
|
|
The system parameters with which @code{syslog} is concerned are arranged
|
|
|
|
in a hierarchical structure like a hierarchical filesystem. To identify
|
|
|
|
a particular parameter, you specify a path through the structure in a
|
|
|
|
way analogous to specifying the pathname of a file. Each component of
|
|
|
|
the path is specified by an integer and each of these integers has a
|
|
|
|
macro defined for it by @file{sysctl.h}. @var{names} is the path, in
|
|
|
|
the form of an array of integers. Each component of the path is one
|
|
|
|
element of the array, in order. @var{nlen} is the number of components
|
|
|
|
in the path.
|
|
|
|
|
|
|
|
For example, the first component of the path for all the paging
|
|
|
|
parameters is the value @code{CTL_VM}. For the free page thresholds, the
|
|
|
|
second component of the path is @code{VM_FREEPG}. So to get the free
|
|
|
|
page threshold values, make @var{names} an array containing the two
|
|
|
|
elements @code{CTL_VM} and @code{VM_FREEPG} and make @var{nlen} = 2.
|
|
|
|
|
|
|
|
|
|
|
|
The format of the value of a parameter depends on the parameter.
|
|
|
|
Sometimes it is an integer; sometimes it is an ASCII string; sometimes
|
|
|
|
it is an elaborate structure. In the case of the free page thresholds
|
|
|
|
used in the example above, the parameter value is a structure containing
|
|
|
|
several integers.
|
|
|
|
|
|
|
|
In any case, you identify a place to return the parameter's value with
|
|
|
|
@var{oldval} and specify the amount of storage available at that
|
|
|
|
location as *@var{oldlenp}. *@var{oldlenp} does double duty because it
|
|
|
|
is also the output location that contains the actual length of the
|
|
|
|
returned value.
|
|
|
|
|
|
|
|
If you don't want the parameter value returned, specify a null pointer
|
|
|
|
for @var{oldval}.
|
|
|
|
|
2000-06-02 02:27:08 +02:00
|
|
|
To set the parameter, specify the address and length of the new value
|
2000-04-30 22:53:48 +02:00
|
|
|
as @var{newval} and @var{newlen}. If you don't want to set the parameter,
|
|
|
|
specify a null pointer as @var{newval}.
|
|
|
|
|
|
|
|
If you get and set a parameter in the same @code{sysctl} call, the value
|
|
|
|
returned is the value of the parameter before it was set.
|
|
|
|
|
|
|
|
Each system parameter has a set of permissions similar to the
|
|
|
|
permissions for a file (including the permissions on directories in its
|
|
|
|
path) that determine whether you may get or set it. For the purposes of
|
|
|
|
these permissions, every parameter is considered to be owned by the
|
|
|
|
superuser and Group 0 so processes with that effective uid or gid may
|
|
|
|
have more access to system parameters. Unlike with files, the superuser
|
|
|
|
does not invariably have full permission to all system parameters, because
|
|
|
|
some of them are designed not to be changed ever.
|
|
|
|
|
|
|
|
|
|
|
|
@code{sysctl} returns a zero return value if it succeeds. Otherwise, it
|
|
|
|
returns @code{-1} and sets @code{errno} appropriately. Besides the
|
|
|
|
failures that apply to all system calls, the following are the
|
|
|
|
@code{errno} codes for all possible failures:
|
|
|
|
|
|
|
|
@table @code
|
|
|
|
@item EPERM
|
2000-06-02 02:27:08 +02:00
|
|
|
The process is not permitted to access one of the components of the
|
2000-04-30 22:53:48 +02:00
|
|
|
path of the system parameter or is not permitted to access the system parameter
|
|
|
|
itself in the way (read or write) that it requested.
|
2000-06-02 02:27:08 +02:00
|
|
|
@c There is some indication in the Linux 2.2 code that the code is trying to
|
2001-05-21 19:38:30 +02:00
|
|
|
@c return EACCES here, but the EACCES value never actually makes it to the
|
2000-04-30 22:53:48 +02:00
|
|
|
@c user.
|
|
|
|
@item ENOTDIR
|
|
|
|
There is no system parameter corresponding to @var{name}.
|
|
|
|
@item EFAULT
|
|
|
|
@var{oldval} is not null, which means the process wanted to read the parameter,
|
|
|
|
but *@var{oldlenp} is zero, so there is no place to return it.
|
|
|
|
@item EINVAL
|
|
|
|
@itemize @bullet
|
|
|
|
@item
|
|
|
|
The process attempted to set a system parameter to a value that is not valid
|
|
|
|
for that parameter.
|
|
|
|
@item
|
|
|
|
The space provided for the return of the system parameter is not the right
|
|
|
|
size for that parameter.
|
|
|
|
@end itemize
|
|
|
|
@item ENOMEM
|
|
|
|
This value may be returned instead of the more correct @code{EINVAL} in some
|
|
|
|
cases where the space provided for the return of the system parameter is too
|
|
|
|
small.
|
|
|
|
|
|
|
|
@end table
|
|
|
|
|
|
|
|
@end deftypefun
|
|
|
|
|
|
|
|
If you have a Linux kernel with the @code{proc} filesystem, you can get
|
2000-06-02 02:27:08 +02:00
|
|
|
and set most of the same parameters by reading and writing to files in
|
2000-04-30 22:53:48 +02:00
|
|
|
the @code{sys} directory of the @code{proc} filesystem. In the @code{sys}
|
|
|
|
directory, the directory structure represents the hierarchical structure
|
|
|
|
of the parameters. E.g. you can display the free page thresholds with
|
|
|
|
@smallexample
|
|
|
|
cat /proc/sys/vm/freepages
|
|
|
|
@end smallexample
|
|
|
|
@c In Linux, the sysctl() and /proc instances of the parameter are created
|
|
|
|
@c together. The proc filesystem accesses the same data structure as
|
|
|
|
@c sysctl(), which has special fields in it for /proc. But it is still
|
|
|
|
@c possible to create a sysctl-only parameter.
|
|
|
|
|
|
|
|
Some more traditional and more widely available, though less general,
|
|
|
|
GNU C library functions for getting and setting some of the same system
|
|
|
|
parameters are:
|
|
|
|
|
|
|
|
@itemize @bullet
|
|
|
|
@item
|
|
|
|
@code{getdomainname}, @code{setdomainname}
|
|
|
|
@item
|
|
|
|
@code{gethostname}, @code{sethostname} (@xref{Host Identification}.)
|
|
|
|
@item
|
2000-05-21 23:22:28 +02:00
|
|
|
@code{uname} (@xref{Platform Type}.)
|
2000-04-30 22:53:48 +02:00
|
|
|
@item
|
|
|
|
@code{bdflush}
|
|
|
|
@end itemize
|