1 /* Substitute for and wrapper around <unistd.h>.
2 Copyright (C) 2004-2008 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20 @PRAGMA_SYSTEM_HEADER@
22 /* The include_next requires a split double-inclusion guard. */
24 # @INCLUDE_NEXT@ @NEXT_UNISTD_H@
30 /* mingw doesn't define the SEEK_* macros in <unistd.h>. */
31 #if !(defined SEEK_CUR && defined SEEK_END && defined SEEK_SET)
35 /* mingw fails to declare _exit in <unistd.h>. */
38 #if @GNULIB_WRITE@ && @REPLACE_WRITE@ && @GNULIB_UNISTD_H_SIGPIPE@
40 # include <sys/types.h>
43 /* The definition of GL_LINK_WARNING is copied here. */
46 /* Declare overridden functions. */
55 # ifndef REPLACE_CHOWN
56 # define REPLACE_CHOWN 1
59 /* Change the owner of FILE to UID (if UID is not -1) and the group of FILE
60 to GID (if GID is not -1). Follow symbolic links.
61 Return 0 if successful, otherwise -1 and errno set.
62 See the POSIX:2001 specification
63 <http://www.opengroup.org/susv3xsh/chown.html>. */
64 # define chown rpl_chown
65 extern int chown (const char *file, uid_t uid, gid_t gid);
68 #elif defined GNULIB_POSIXCHECK
70 # define chown(f,u,g) \
71 (GL_LINK_WARNING ("chown fails to follow symlinks on some systems and " \
72 "doesn't treat a uid or gid of -1 on some systems - " \
73 "use gnulib module chown for portability"), \
80 /* Copy the file descriptor OLDFD into file descriptor NEWFD. Do nothing if
81 NEWFD = OLDFD, otherwise close NEWFD first if it is open.
82 Return 0 if successful, otherwise -1 and errno set.
83 See the POSIX:2001 specification
84 <http://www.opengroup.org/susv3xsh/dup2.html>. */
85 extern int dup2 (int oldfd, int newfd);
87 #elif defined GNULIB_POSIXCHECK
90 (GL_LINK_WARNING ("dup2 is unportable - " \
91 "use gnulib module dup2 for portability"), \
97 # if !@HAVE_DECL_ENVIRON@
98 /* Set of environment variables and values. An array of strings of the form
99 "VARIABLE=VALUE", terminated with a NULL. */
100 # if defined __APPLE__ && defined __MACH__
101 # include <crt_externs.h>
102 # define environ (*_NSGetEnviron ())
104 extern char **environ;
107 #elif defined GNULIB_POSIXCHECK
110 (GL_LINK_WARNING ("environ is unportable - " \
111 "use gnulib module environ for portability"), \
117 # if @REPLACE_FCHDIR@
119 /* Change the process' current working directory to the directory on which
120 the given file descriptor is open.
121 Return 0 if successful, otherwise -1 and errno set.
122 See the POSIX:2001 specification
123 <http://www.opengroup.org/susv3xsh/fchdir.html>. */
124 extern int fchdir (int /*fd*/);
126 # define close rpl_close
127 extern int close (int);
129 extern int dup (int);
130 # define dup2 rpl_dup2
131 extern int dup2 (int, int);
134 #elif defined GNULIB_POSIXCHECK
137 (GL_LINK_WARNING ("fchdir is unportable - " \
138 "use gnulib module fchdir for portability"), \
143 #if @GNULIB_FTRUNCATE@
144 # if !@HAVE_FTRUNCATE@
145 /* Change the size of the file to which FD is opened to become equal to LENGTH.
146 Return 0 if successful, otherwise -1 and errno set.
147 See the POSIX:2001 specification
148 <http://www.opengroup.org/susv3xsh/ftruncate.html>. */
149 extern int ftruncate (int fd, off_t length);
151 #elif defined GNULIB_POSIXCHECK
153 # define ftruncate(f,l) \
154 (GL_LINK_WARNING ("ftruncate is unportable - " \
155 "use gnulib module ftruncate for portability"), \
161 /* Include the headers that might declare getcwd so that they will not
162 cause confusion if included after this file. */
164 # if @REPLACE_GETCWD@
165 /* Get the name of the current working directory, and put it in SIZE bytes
167 Return BUF if successful, or NULL if the directory couldn't be determined
168 or SIZE was too small.
169 See the POSIX:2001 specification
170 <http://www.opengroup.org/susv3xsh/getcwd.html>.
171 Additionally, the gnulib module 'getcwd' guarantees the following GNU
172 extension: If BUF is NULL, an array is allocated with 'malloc'; the array
173 is SIZE bytes long, unless SIZE == 0, in which case it is as big as
175 # define getcwd rpl_getcwd
176 extern char * getcwd (char *buf, size_t size);
178 #elif defined GNULIB_POSIXCHECK
180 # define getcwd(b,s) \
181 (GL_LINK_WARNING ("getcwd is unportable - " \
182 "use gnulib module getcwd for portability"), \
187 #if @GNULIB_GETLOGIN_R@
188 /* Copies the user's login name to NAME.
189 The array pointed to by NAME has room for SIZE bytes.
191 Returns 0 if successful. Upon error, an error number is returned, or -1 in
192 the case that the login name cannot be found but no specific error is
193 provided (this case is hopefully rare but is left open by the POSIX spec).
195 See <http://www.opengroup.org/susv3xsh/getlogin.html>.
197 # if !@HAVE_DECL_GETLOGIN_R@
199 extern int getlogin_r (char *name, size_t size);
201 #elif defined GNULIB_POSIXCHECK
203 # define getlogin_r(n,s) \
204 (GL_LINK_WARNING ("getlogin_r is unportable - " \
205 "use gnulib module getlogin_r for portability"), \
210 #if @GNULIB_GETPAGESIZE@
211 # if @REPLACE_GETPAGESIZE@
212 # define getpagesize rpl_getpagesize
213 extern int getpagesize (void);
214 # elif !@HAVE_GETPAGESIZE@
215 /* This is for POSIX systems. */
216 # if !defined getpagesize && defined _SC_PAGESIZE
217 # if ! (defined __VMS && __VMS_VER < 70000000)
218 # define getpagesize() sysconf (_SC_PAGESIZE)
221 /* This is for older VMS. */
222 # if !defined getpagesize && defined __VMS
224 # define getpagesize() 8192
226 # define getpagesize() 512
229 /* This is for BeOS. */
230 # if !defined getpagesize && @HAVE_OS_H@
232 # if defined B_PAGE_SIZE
233 # define getpagesize() B_PAGE_SIZE
236 /* This is for AmigaOS4.0. */
237 # if !defined getpagesize && defined __amigaos4__
238 # define getpagesize() 2048
240 /* This is for older Unix systems. */
241 # if !defined getpagesize && @HAVE_SYS_PARAM_H@
242 # include <sys/param.h>
243 # ifdef EXEC_PAGESIZE
244 # define getpagesize() EXEC_PAGESIZE
250 # define getpagesize() (NBPG * CLSIZE)
253 # define getpagesize() NBPC
259 #elif defined GNULIB_POSIXCHECK
261 # define getpagesize() \
262 (GL_LINK_WARNING ("getpagesize is unportable - " \
263 "use gnulib module getpagesize for portability"), \
269 # if @REPLACE_LCHOWN@
270 /* Change the owner of FILE to UID (if UID is not -1) and the group of FILE
271 to GID (if GID is not -1). Do not follow symbolic links.
272 Return 0 if successful, otherwise -1 and errno set.
273 See the POSIX:2001 specification
274 <http://www.opengroup.org/susv3xsh/lchown.html>. */
275 # define lchown rpl_lchown
276 extern int lchown (char const *file, uid_t owner, gid_t group);
278 #elif defined GNULIB_POSIXCHECK
280 # define lchown(f,u,g) \
281 (GL_LINK_WARNING ("lchown is unportable to pre-POSIX.1-2001 " \
282 "systems - use gnulib module lchown for portability"), \
289 /* Set the offset of FD relative to SEEK_SET, SEEK_CUR, or SEEK_END.
290 Return the new offset if successful, otherwise -1 and errno set.
291 See the POSIX:2001 specification
292 <http://www.opengroup.org/susv3xsh/lseek.html>. */
293 # define lseek rpl_lseek
294 extern off_t lseek (int fd, off_t offset, int whence);
296 #elif defined GNULIB_POSIXCHECK
298 # define lseek(f,o,w) \
299 (GL_LINK_WARNING ("lseek does not fail with ESPIPE on pipes on some " \
300 "systems - use gnulib module lseek for portability"), \
305 #if @GNULIB_READLINK@
306 /* Read the contents of the symbolic link FILE and place the first BUFSIZE
307 bytes of it into BUF. Return the number of bytes placed into BUF if
308 successful, otherwise -1 and errno set.
309 See the POSIX:2001 specification
310 <http://www.opengroup.org/susv3xsh/readlink.html>. */
311 # if !@HAVE_READLINK@
313 extern int readlink (const char *file, char *buf, size_t bufsize);
315 #elif defined GNULIB_POSIXCHECK
317 # define readlink(f,b,s) \
318 (GL_LINK_WARNING ("readlink is unportable - " \
319 "use gnulib module readlink for portability"), \
325 /* Pause the execution of the current thread for N seconds.
326 Returns the number of seconds left to sleep.
327 See the POSIX:2001 specification
328 <http://www.opengroup.org/susv3xsh/sleep.html>. */
330 extern unsigned int sleep (unsigned int n);
332 #elif defined GNULIB_POSIXCHECK
335 (GL_LINK_WARNING ("sleep is unportable - " \
336 "use gnulib module sleep for portability"), \
341 #if @GNULIB_WRITE@ && @REPLACE_WRITE@ && @GNULIB_UNISTD_H_SIGPIPE@
342 /* Write up to COUNT bytes starting at BUF to file descriptor FD.
343 See the POSIX:2001 specification
344 <http://www.opengroup.org/susv3xsh/write.html>. */
346 # define write rpl_write
347 extern ssize_t write (int fd, const void *buf, size_t count);
356 #endif /* _GL_UNISTD_H */
357 #endif /* _GL_UNISTD_H */