Auto merge of #733 - Susurrus:fexecve, r=alexcrichton

Remove fexecvpe from Haiku and MacOS/IOS where it's not implemented

I was going to remove the skip-check from `build.rs` to see if we might be able to enable the function check on at least some platforms, but I'll assume it doesn't work on any as has been suggested.

Closes #732.

src/unix/bsd/freebsdlike/mod.rs

@@ -1107,6 +1107,9 @@ extern {
                  timeout: *const ::timespec,
                  sigmask: *const sigset_t) -> ::c_int;
     pub fn settimeofday(tv: *const ::timeval, tz: *const ::timezone) -> ::c_int;
+    pub fn fexecve(fd: ::c_int, argv: *const *const ::c_char,
+                   envp: *const *const ::c_char)
+                   -> ::c_int;
 }
 
 cfg_if! {

src/unix/bsd/netbsdlike/mod.rs

@@ -622,6 +622,9 @@ extern {
                         groups: *mut ::gid_t,
                         ngroups: *mut ::c_int) -> ::c_int;
     pub fn initgroups(name: *const ::c_char, basegid: ::gid_t) -> ::c_int;
+    pub fn fexecve(fd: ::c_int, argv: *const *const ::c_char,
+                   envp: *const *const ::c_char)
+                   -> ::c_int;
 }
 
 cfg_if! {

src/unix/mod.rs

@@ -479,9 +479,6 @@ extern {
                   -> ::c_int;
     pub fn execvp(c: *const c_char,
                   argv: *const *const c_char) -> ::c_int;
-    pub fn fexecve(fd: ::c_int, argv: *const *const c_char,
-                   envp: *const *const c_char)
-                   -> ::c_int;
     pub fn fork() -> pid_t;
     pub fn fpathconf(filedes: ::c_int, name: ::c_int) -> c_long;
     pub fn getcwd(buf: *mut c_char, size: ::size_t) -> *mut c_char;

src/unix/newlib/mod.rs

@@ -586,6 +586,9 @@ extern {
                        serv: *mut ::c_char, servlen: socklen_t,
                        flags: ::c_int) -> ::c_int;
     pub fn memalign(align: ::size_t, size: ::size_t) -> *mut ::c_void;
+    pub fn fexecve(fd: ::c_int, argv: *const *const ::c_char,
+                   envp: *const *const ::c_char)
+                   -> ::c_int;
 }
 
 cfg_if! {

src/unix/notbsd/mod.rs

@@ -1062,6 +1062,9 @@ extern {
                 winp: *const ::winsize) -> ::pid_t;
     pub fn execvpe(file: *const ::c_char, argv: *const *const ::c_char,
                    envp: *const *const ::c_char) -> ::c_int;
+    pub fn fexecve(fd: ::c_int, argv: *const *const ::c_char,
+                   envp: *const *const ::c_char)
+                   -> ::c_int;
 }
 
 cfg_if! {

src/unix/solaris/mod.rs

@@ -1278,4 +1278,7 @@ extern {
     pub fn port_getn(port: ::c_int, pe_list: *mut port_event, max: ::c_uint,
                      nget: *mut ::c_uint, timeout: *const ::timespec)
                      -> ::c_int;
+    pub fn fexecve(fd: ::c_int, argv: *const *const ::c_char,
+                   envp: *const *const ::c_char)
+                   -> ::c_int;
 }