ddf1e65262
libstdc++/2071 * porting.texi: Add documentation about libstdc++-v3-specific macros that are currently included in os_defines.h files. * config/basic_file_stdio.h (sys_getc): New method. (sys_ungetc): New method. * include/bits/basic_file.h: (sys_getc): New method signature. (sys_ungetc): New method signature. * include/bits/fstream.tcc (underflow): Add conditional code paths which avoid using short seeks on streams (especially useful when the stream might be interactive or a pipe). At the moment, this alternate path only avoids seeking when the ``buffer size'' of underflow() is 1 since the C standard only guarantees buffer space for one ungetc (this technique could be extended since *-*-solaris* supports buffering for 4 calls to ungetc and *-*-*bsd* supports buffering limited only by memory resources). Also, _GLIBCPP_AVOID_FSEEK must be defined in a port's os_defines.h file for this alternate path to even be considered. As a bonus, the idiom of using getc/ungetc requires no system calls whereas fseek maps to one or two system call(s) on many platforms. * config/os/bsd/freebsd/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Define it. * config/os/solaris/solaris2.5/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.6/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. * config/os/solaris/solaris2.7/bits/os_defines.h (_GLIBCPP_AVOID_FSEEK): Likewise. From-SVN: r43278 |
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| ctype_base.h | ||
| ctype_inline.h | ||
| ctype_noninline.h | ||
| os_defines.h | ||