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   1/* Copyright (C) 1991-2025 Free Software Foundation, Inc.
   2   This file is part of the GNU C Library.
   3
   4   The GNU C Library is free software; you can redistribute it and/or
   5   modify it under the terms of the GNU Lesser General Public
   6   License as published by the Free Software Foundation; either
   7   version 2.1 of the License, or (at your option) any later version.
   8
   9   The GNU C Library 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 GNU
  12   Lesser General Public License for more details.
  13
  14   You should have received a copy of the GNU Lesser General Public
  15   License along with the GNU C Library; if not, see
  16   <https://www.gnu.org/licenses/>.  */
  17
  18/*
  19 *	POSIX Standard: 2.10 Symbolic Constants		<unistd.h>
  20 */
  21
  22#ifndef	_UNISTD_H
  23#define	_UNISTD_H	1
  24
  25#include <features.h>
  26
  27__BEGIN_DECLS
  28
  29/* These may be used to determine what facilities are present at compile time.
  30   Their values can be obtained at run time from `sysconf'.  */
  31
  32#ifdef __USE_XOPEN2K8
  33/* POSIX Standard approved as ISO/IEC 9945-1 as of September 2008.  */
  34# define _POSIX_VERSION	200809L
  35#elif defined __USE_XOPEN2K
  36/* POSIX Standard approved as ISO/IEC 9945-1 as of December 2001.  */
  37# define _POSIX_VERSION	200112L
  38#elif defined __USE_POSIX199506
  39/* POSIX Standard approved as ISO/IEC 9945-1 as of June 1995.  */
  40# define _POSIX_VERSION	199506L
  41#elif defined __USE_POSIX199309
  42/* POSIX Standard approved as ISO/IEC 9945-1 as of September 1993.  */
  43# define _POSIX_VERSION	199309L
  44#else
  45/* POSIX Standard approved as ISO/IEC 9945-1 as of September 1990.  */
  46# define _POSIX_VERSION	199009L
  47#endif
  48
  49/* These are not #ifdef __USE_POSIX2 because they are
  50   in the theoretically application-owned namespace.  */
  51
  52#ifdef __USE_XOPEN2K8
  53# define __POSIX2_THIS_VERSION	200809L
  54/* The utilities on GNU systems also correspond to this version.  */
  55#elif defined __USE_XOPEN2K
  56/* The utilities on GNU systems also correspond to this version.  */
  57# define __POSIX2_THIS_VERSION	200112L
  58#elif defined __USE_POSIX199506
  59/* The utilities on GNU systems also correspond to this version.  */
  60# define __POSIX2_THIS_VERSION	199506L
  61#else
  62/* The utilities on GNU systems also correspond to this version.  */
  63# define __POSIX2_THIS_VERSION	199209L
  64#endif
  65
  66/* The utilities on GNU systems also correspond to this version.  */
  67#define _POSIX2_VERSION	__POSIX2_THIS_VERSION
  68
  69/* This symbol was required until the 2001 edition of POSIX.  */
  70#define	_POSIX2_C_VERSION	__POSIX2_THIS_VERSION
  71
  72/* If defined, the implementation supports the
  73   C Language Bindings Option.  */
  74#define	_POSIX2_C_BIND	__POSIX2_THIS_VERSION
  75
  76/* If defined, the implementation supports the
  77   C Language Development Utilities Option.  */
  78#define	_POSIX2_C_DEV	__POSIX2_THIS_VERSION
  79
  80/* If defined, the implementation supports the
  81   Software Development Utilities Option.  */
  82#define	_POSIX2_SW_DEV	__POSIX2_THIS_VERSION
  83
  84/* If defined, the implementation supports the
  85   creation of locales with the localedef utility.  */
  86#define _POSIX2_LOCALEDEF       __POSIX2_THIS_VERSION
  87
  88/* X/Open version number to which the library conforms.  It is selectable.  */
  89#ifdef __USE_XOPEN2K8
  90# define _XOPEN_VERSION	700
  91#elif defined __USE_XOPEN2K
  92# define _XOPEN_VERSION	600
  93#elif defined __USE_UNIX98
  94# define _XOPEN_VERSION	500
  95#else
  96# define _XOPEN_VERSION	4
  97#endif
  98
  99/* Commands and utilities from XPG4 are available.  */
 100#define _XOPEN_XCU_VERSION	4
 101
 102/* We are compatible with the old published standards as well.  */
 103#define _XOPEN_XPG2	1
 104#define _XOPEN_XPG3	1
 105#define _XOPEN_XPG4	1
 106
 107/* The X/Open Unix extensions are available.  */
 108#define _XOPEN_UNIX	1
 109
 110/* The enhanced internationalization capabilities according to XPG4.2
 111   are present.  */
 112#define	_XOPEN_ENH_I18N	1
 113
 114/* The legacy interfaces are also available.  */
 115#define _XOPEN_LEGACY	1
 116
 117
 118/* Get values of POSIX options:
 119
 120   If these symbols are defined, the corresponding features are
 121   always available.  If not, they may be available sometimes.
 122   The current values can be obtained with `sysconf'.
 123
 124   _POSIX_JOB_CONTROL		Job control is supported.
 125   _POSIX_SAVED_IDS		Processes have a saved set-user-ID
 126				and a saved set-group-ID.
 127   _POSIX_REALTIME_SIGNALS	Real-time, queued signals are supported.
 128   _POSIX_PRIORITY_SCHEDULING	Priority scheduling is supported.
 129   _POSIX_TIMERS		POSIX.4 clocks and timers are supported.
 130   _POSIX_ASYNCHRONOUS_IO	Asynchronous I/O is supported.
 131   _POSIX_PRIORITIZED_IO	Prioritized asynchronous I/O is supported.
 132   _POSIX_SYNCHRONIZED_IO	Synchronizing file data is supported.
 133   _POSIX_FSYNC			The fsync function is present.
 134   _POSIX_MAPPED_FILES		Mapping of files to memory is supported.
 135   _POSIX_MEMLOCK		Locking of all memory is supported.
 136   _POSIX_MEMLOCK_RANGE		Locking of ranges of memory is supported.
 137   _POSIX_MEMORY_PROTECTION	Setting of memory protections is supported.
 138   _POSIX_MESSAGE_PASSING	POSIX.4 message queues are supported.
 139   _POSIX_SEMAPHORES		POSIX.4 counting semaphores are supported.
 140   _POSIX_SHARED_MEMORY_OBJECTS	POSIX.4 shared memory objects are supported.
 141   _POSIX_THREADS		POSIX.1c pthreads are supported.
 142   _POSIX_THREAD_ATTR_STACKADDR	Thread stack address attribute option supported.
 143   _POSIX_THREAD_ATTR_STACKSIZE	Thread stack size attribute option supported.
 144   _POSIX_THREAD_SAFE_FUNCTIONS	Thread-safe functions are supported.
 145   _POSIX_THREAD_PRIORITY_SCHEDULING
 146				POSIX.1c thread execution scheduling supported.
 147   _POSIX_THREAD_PRIO_INHERIT	Thread priority inheritance option supported.
 148   _POSIX_THREAD_PRIO_PROTECT	Thread priority protection option supported.
 149   _POSIX_THREAD_PROCESS_SHARED	Process-shared synchronization supported.
 150   _POSIX_PII			Protocol-independent interfaces are supported.
 151   _POSIX_PII_XTI		XTI protocol-indep. interfaces are supported.
 152   _POSIX_PII_SOCKET		Socket protocol-indep. interfaces are supported.
 153   _POSIX_PII_INTERNET		Internet family of protocols supported.
 154   _POSIX_PII_INTERNET_STREAM	Connection-mode Internet protocol supported.
 155   _POSIX_PII_INTERNET_DGRAM	Connectionless Internet protocol supported.
 156   _POSIX_PII_OSI		ISO/OSI family of protocols supported.
 157   _POSIX_PII_OSI_COTS		Connection-mode ISO/OSI service supported.
 158   _POSIX_PII_OSI_CLTS		Connectionless ISO/OSI service supported.
 159   _POSIX_POLL			Implementation supports `poll' function.
 160   _POSIX_SELECT		Implementation supports `select' and `pselect'.
 161
 162   _XOPEN_REALTIME		X/Open realtime support is available.
 163   _XOPEN_REALTIME_THREADS	X/Open realtime thread support is available.
 164   _XOPEN_SHM			Shared memory interface according to XPG4.2.
 165
 166   _XBS5_ILP32_OFF32		Implementation provides environment with 32-bit
 167				int, long, pointer, and off_t types.
 168   _XBS5_ILP32_OFFBIG		Implementation provides environment with 32-bit
 169				int, long, and pointer and off_t with at least
 170				64 bits.
 171   _XBS5_LP64_OFF64		Implementation provides environment with 32-bit
 172				int, and 64-bit long, pointer, and off_t types.
 173   _XBS5_LPBIG_OFFBIG		Implementation provides environment with at
 174				least 32 bits int and long, pointer, and off_t
 175				with at least 64 bits.
 176
 177   If any of these symbols is defined as -1, the corresponding option is not
 178   true for any file.  If any is defined as other than -1, the corresponding
 179   option is true for all files.  If a symbol is not defined at all, the value
 180   for a specific file can be obtained from `pathconf' and `fpathconf'.
 181
 182   _POSIX_CHOWN_RESTRICTED	Only the super user can use `chown' to change
 183				the owner of a file.  `chown' can only be used
 184				to change the group ID of a file to a group of
 185				which the calling process is a member.
 186   _POSIX_NO_TRUNC		Pathname components longer than
 187				NAME_MAX generate an error.
 188   _POSIX_VDISABLE		If defined, if the value of an element of the
 189				`c_cc' member of `struct termios' is
 190				_POSIX_VDISABLE, no character will have the
 191				effect associated with that element.
 192   _POSIX_SYNC_IO		Synchronous I/O may be performed.
 193   _POSIX_ASYNC_IO		Asynchronous I/O may be performed.
 194   _POSIX_PRIO_IO		Prioritized Asynchronous I/O may be performed.
 195
 196   Support for the Large File Support interface is not generally available.
 197   If it is available the following constants are defined to one.
 198   _LFS64_LARGEFILE		Low-level I/O supports large files.
 199   _LFS64_STDIO			Standard I/O supports large files.
 200   */
 201
 202#include <bits/posix_opt.h>
 203
 204/* Get the environment definitions from Unix98.  */
 205#if defined __USE_UNIX98 || defined __USE_XOPEN2K
 206# include <bits/environments.h>
 207#endif
 208
 209/* Standard file descriptors.  */
 210#define	STDIN_FILENO	0	/* Standard input.  */
 211#define	STDOUT_FILENO	1	/* Standard output.  */
 212#define	STDERR_FILENO	2	/* Standard error output.  */
 213
 214
 215/* All functions that are not declared anywhere else.  */
 216
 217#include <bits/types.h>
 218
 219#ifndef	__ssize_t_defined
 220typedef __ssize_t ssize_t;
 221# define __ssize_t_defined
 222#endif
 223
 224#define	__need_size_t
 225#define __need_NULL
 226#include <stddef.h>
 227
 228#if defined __USE_XOPEN || defined __USE_XOPEN2K
 229/* The Single Unix specification says that some more types are
 230   available here.  */
 231# ifndef __gid_t_defined
 232typedef __gid_t gid_t;
 233#  define __gid_t_defined
 234# endif
 235
 236# ifndef __uid_t_defined
 237typedef __uid_t uid_t;
 238#  define __uid_t_defined
 239# endif
 240
 241# ifndef __off_t_defined
 242#  ifndef __USE_FILE_OFFSET64
 243typedef __off_t off_t;
 244#  else
 245typedef __off64_t off_t;
 246#  endif
 247#  define __off_t_defined
 248# endif
 249# if defined __USE_LARGEFILE64 && !defined __off64_t_defined
 250typedef __off64_t off64_t;
 251#  define __off64_t_defined
 252# endif
 253
 254# ifndef __useconds_t_defined
 255typedef __useconds_t useconds_t;
 256#  define __useconds_t_defined
 257# endif
 258
 259# ifndef __pid_t_defined
 260typedef __pid_t pid_t;
 261#  define __pid_t_defined
 262# endif
 263#endif	/* X/Open */
 264
 265#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
 266# ifndef __intptr_t_defined
 267typedef __intptr_t intptr_t;
 268#  define __intptr_t_defined
 269# endif
 270#endif
 271
 272#if defined __USE_MISC || defined __USE_XOPEN
 273# ifndef __socklen_t_defined
 274typedef __socklen_t socklen_t;
 275#  define __socklen_t_defined
 276# endif
 277#endif
 278
 279/* Values for the second argument to access.
 280   These may be OR'd together.  */
 281#define	R_OK	4		/* Test for read permission.  */
 282#define	W_OK	2		/* Test for write permission.  */
 283#define	X_OK	1		/* Test for execute permission.  */
 284#define	F_OK	0		/* Test for existence.  */
 285
 286/* Test for access to NAME using the real UID and real GID.  */
 287extern int access (const char *__name, int __type) __THROW __nonnull ((1));
 288
 289#ifdef __USE_GNU
 290/* Test for access to NAME using the effective UID and GID
 291   (as normal file operations use).  */
 292extern int euidaccess (const char *__name, int __type)
 293     __THROW __nonnull ((1));
 294
 295/* An alias for `euidaccess', used by some other systems.  */
 296extern int eaccess (const char *__name, int __type)
 297     __THROW __nonnull ((1));
 298
 299/* Execute program relative to a directory file descriptor.  */
 300extern int execveat (int __fd, const char *__path, char *const __argv[],
 301                     char *const __envp[], int __flags)
 302    __THROW __nonnull ((2, 3));
 303#endif
 304
 305#ifdef __USE_ATFILE
 306/* Test for access to FILE relative to the directory FD is open on.
 307   If AT_EACCESS is set in FLAG, then use effective IDs like `eaccess',
 308   otherwise use real IDs like `access'.  */
 309extern int faccessat (int __fd, const char *__file, int __type, int __flag)
 310     __THROW __nonnull ((2)) __wur;
 311#endif /* Use GNU.  */
 312
 313
 314/* Values for the WHENCE argument to lseek.  */
 315#ifndef	_STDIO_H		/* <stdio.h> has the same definitions.  */
 316# define SEEK_SET	0	/* Seek from beginning of file.  */
 317# define SEEK_CUR	1	/* Seek from current position.  */
 318# define SEEK_END	2	/* Seek from end of file.  */
 319# ifdef __USE_GNU
 320#  define SEEK_DATA	3	/* Seek to next data.  */
 321#  define SEEK_HOLE	4	/* Seek to next hole.  */
 322# endif
 323#endif
 324
 325#if defined __USE_MISC && !defined L_SET
 326/* Old BSD names for the same constants; just for compatibility.  */
 327# define L_SET		SEEK_SET
 328# define L_INCR		SEEK_CUR
 329# define L_XTND		SEEK_END
 330#endif
 331
 332
 333/* Move FD's file position to OFFSET bytes from the
 334   beginning of the file (if WHENCE is SEEK_SET),
 335   the current position (if WHENCE is SEEK_CUR),
 336   or the end of the file (if WHENCE is SEEK_END).
 337   Return the new file position.  */
 338#ifndef __USE_FILE_OFFSET64
 339extern __off_t lseek (int __fd, __off_t __offset, int __whence) __THROW;
 340#else
 341# ifdef __REDIRECT_NTH
 342extern __off64_t __REDIRECT_NTH (lseek,
 343				 (int __fd, __off64_t __offset, int __whence),
 344				 lseek64);
 345# else
 346#  define lseek lseek64
 347# endif
 348#endif
 349#ifdef __USE_LARGEFILE64
 350extern __off64_t lseek64 (int __fd, __off64_t __offset, int __whence)
 351     __THROW;
 352#endif
 353
 354/* Close the file descriptor FD.
 355
 356   This function is a cancellation point and therefore not marked with
 357   __THROW.  */
 358extern int close (int __fd);
 359
 360#ifdef __USE_MISC
 361/* Close all open file descriptors greater than or equal to LOWFD.
 362   Negative LOWFD is clamped to 0.  */
 363extern void closefrom (int __lowfd) __THROW;
 364#endif
 365
 366/* Read NBYTES into BUF from FD.  Return the
 367   number read, -1 for errors or 0 for EOF.
 368
 369   This function is a cancellation point and therefore not marked with
 370   __THROW.  */
 371extern ssize_t read (int __fd, void *__buf, size_t __nbytes) __wur
 372    __fortified_attr_access (__write_only__, 2, 3);
 373
 374/* Write N bytes of BUF to FD.  Return the number written, or -1.
 375
 376   This function is a cancellation point and therefore not marked with
 377   __THROW.  */
 378extern ssize_t write (int __fd, const void *__buf, size_t __n) __wur
 379    __attr_access ((__read_only__, 2, 3));
 380
 381#if defined __USE_UNIX98 || defined __USE_XOPEN2K8
 382# ifndef __USE_FILE_OFFSET64
 383/* Read NBYTES into BUF from FD at the given position OFFSET without
 384   changing the file pointer.  Return the number read, -1 for errors
 385   or 0 for EOF.
 386
 387   This function is a cancellation point and therefore not marked with
 388   __THROW.  */
 389extern ssize_t pread (int __fd, void *__buf, size_t __nbytes,
 390		      __off_t __offset) __wur
 391    __fortified_attr_access (__write_only__, 2, 3);
 392
 393/* Write N bytes of BUF to FD at the given position OFFSET without
 394   changing the file pointer.  Return the number written, or -1.
 395
 396   This function is a cancellation point and therefore not marked with
 397   __THROW.  */
 398extern ssize_t pwrite (int __fd, const void *__buf, size_t __n,
 399		       __off_t __offset) __wur
 400    __attr_access ((__read_only__, 2, 3));
 401
 402# else
 403#  ifdef __REDIRECT
 404extern ssize_t __REDIRECT (pread, (int __fd, void *__buf, size_t __nbytes,
 405				   __off64_t __offset),
 406			   pread64) __wur
 407    __fortified_attr_access (__write_only__, 2, 3);
 408extern ssize_t __REDIRECT (pwrite, (int __fd, const void *__buf,
 409				    size_t __nbytes, __off64_t __offset),
 410			   pwrite64) __wur
 411    __attr_access ((__read_only__, 2, 3));
 412#  else
 413#   define pread pread64
 414#   define pwrite pwrite64
 415#  endif
 416# endif
 417
 418# ifdef __USE_LARGEFILE64
 419/* Read NBYTES into BUF from FD at the given position OFFSET without
 420   changing the file pointer.  Return the number read, -1 for errors
 421   or 0 for EOF.  */
 422extern ssize_t pread64 (int __fd, void *__buf, size_t __nbytes,
 423			__off64_t __offset) __wur
 424    __fortified_attr_access (__write_only__, 2, 3);
 425/* Write N bytes of BUF to FD at the given position OFFSET without
 426   changing the file pointer.  Return the number written, or -1.  */
 427extern ssize_t pwrite64 (int __fd, const void *__buf, size_t __n,
 428			 __off64_t __offset) __wur
 429    __attr_access ((__read_only__, 2, 3));
 430# endif
 431#endif
 432
 433/* Create a one-way communication channel (pipe).
 434   If successful, two file descriptors are stored in PIPEDES;
 435   bytes written on PIPEDES[1] can be read from PIPEDES[0].
 436   Returns 0 if successful, -1 if not.  */
 437extern int pipe (int __pipedes[2]) __THROW __wur;
 438
 439#ifdef __USE_GNU
 440/* Same as pipe but apply flags passed in FLAGS to the new file
 441   descriptors.  */
 442extern int pipe2 (int __pipedes[2], int __flags) __THROW __wur;
 443#endif
 444
 445/* Schedule an alarm.  In SECONDS seconds, the process will get a SIGALRM.
 446   If SECONDS is zero, any currently scheduled alarm will be cancelled.
 447   The function returns the number of seconds remaining until the last
 448   alarm scheduled would have signaled, or zero if there wasn't one.
 449   There is no return value to indicate an error, but you can set `errno'
 450   to 0 and check its value after calling `alarm', and this might tell you.
 451   The signal may come late due to processor scheduling.  */
 452extern unsigned int alarm (unsigned int __seconds) __THROW;
 453
 454/* Make the process sleep for SECONDS seconds, or until a signal arrives
 455   and is not ignored.  The function returns the number of seconds less
 456   than SECONDS which it actually slept (thus zero if it slept the full time).
 457   If a signal handler does a `longjmp' or modifies the handling of the
 458   SIGALRM signal while inside `sleep' call, the handling of the SIGALRM
 459   signal afterwards is undefined.  There is no return value to indicate
 460   error, but if `sleep' returns SECONDS, it probably didn't work.
 461
 462   This function is a cancellation point and therefore not marked with
 463   __THROW.  */
 464extern unsigned int sleep (unsigned int __seconds);
 465
 466#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
 467    || defined __USE_MISC
 468/* Set an alarm to go off (generating a SIGALRM signal) in VALUE
 469   microseconds.  If INTERVAL is nonzero, when the alarm goes off, the
 470   timer is reset to go off every INTERVAL microseconds thereafter.
 471   Returns the number of microseconds remaining before the alarm.  */
 472extern __useconds_t ualarm (__useconds_t __value, __useconds_t __interval)
 473     __THROW;
 474
 475/* Sleep USECONDS microseconds, or until a signal arrives that is not blocked
 476   or ignored.
 477
 478   This function is a cancellation point and therefore not marked with
 479   __THROW.  */
 480extern int usleep (__useconds_t __useconds);
 481#endif
 482
 483
 484/* Suspend the process until a signal arrives.
 485   This always returns -1 and sets `errno' to EINTR.
 486
 487   This function is a cancellation point and therefore not marked with
 488   __THROW.  */
 489extern int pause (void);
 490
 491
 492/* Change the owner and group of FILE.  */
 493extern int chown (const char *__file, __uid_t __owner, __gid_t __group)
 494     __THROW __nonnull ((1)) __wur;
 495
 496#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
 497/* Change the owner and group of the file that FD is open on.  */
 498extern int fchown (int __fd, __uid_t __owner, __gid_t __group) __THROW __wur;
 499
 500
 501/* Change owner and group of FILE, if it is a symbolic
 502   link the ownership of the symbolic link is changed.  */
 503extern int lchown (const char *__file, __uid_t __owner, __gid_t __group)
 504     __THROW __nonnull ((1)) __wur;
 505
 506#endif /* Use X/Open Unix.  */
 507
 508#ifdef __USE_ATFILE
 509/* Change the owner and group of FILE relative to the directory FD is open
 510   on.  */
 511extern int fchownat (int __fd, const char *__file, __uid_t __owner,
 512		     __gid_t __group, int __flag)
 513     __THROW __nonnull ((2)) __wur;
 514#endif /* Use GNU.  */
 515
 516/* Change the process's working directory to PATH.  */
 517extern int chdir (const char *__path) __THROW __nonnull ((1)) __wur;
 518
 519#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
 520/* Change the process's working directory to the one FD is open on.  */
 521extern int fchdir (int __fd) __THROW __wur;
 522#endif
 523
 524/* Get the pathname of the current working directory,
 525   and put it in SIZE bytes of BUF.  Returns NULL if the
 526   directory couldn't be determined or SIZE was too small.
 527   If successful, returns BUF.  In GNU, if BUF is NULL,
 528   an array is allocated with `malloc'; the array is SIZE
 529   bytes long, unless SIZE == 0, in which case it is as
 530   big as necessary.  */
 531extern char *getcwd (char *__buf, size_t __size) __THROW __wur;
 532
 533#ifdef	__USE_GNU
 534/* Return a malloc'd string containing the current directory name.
 535   If the environment variable `PWD' is set, and its value is correct,
 536   that value is used.  */
 537extern char *get_current_dir_name (void) __THROW;
 538#endif
 539
 540#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
 541    || defined __USE_MISC
 542/* Put the absolute pathname of the current working directory in BUF.
 543   If successful, return BUF.  If not, put an error message in
 544   BUF and return NULL.  BUF should be at least PATH_MAX bytes long.  */
 545extern char *getwd (char *__buf)
 546     __THROW __nonnull ((1)) __attribute_deprecated__ __wur
 547    __attr_access ((__write_only__, 1));
 548#endif
 549
 550
 551/* Duplicate FD, returning a new file descriptor on the same file.  */
 552extern int dup (int __fd) __THROW __wur;
 553
 554/* Duplicate FD to FD2, closing FD2 and making it open on the same file.  */
 555extern int dup2 (int __fd, int __fd2) __THROW;
 556
 557#ifdef __USE_GNU
 558/* Duplicate FD to FD2, closing FD2 and making it open on the same
 559   file while setting flags according to FLAGS.  */
 560extern int dup3 (int __fd, int __fd2, int __flags) __THROW;
 561#endif
 562
 563/* NULL-terminated array of "NAME=VALUE" environment variables.  */
 564extern char **__environ;
 565#ifdef __USE_GNU
 566extern char **environ;
 567#endif
 568
 569
 570/* Replace the current process, executing PATH with arguments ARGV and
 571   environment ENVP.  ARGV and ENVP are terminated by NULL pointers.  */
 572extern int execve (const char *__path, char *const __argv[],
 573		   char *const __envp[]) __THROW __nonnull ((1, 2));
 574
 575#ifdef __USE_XOPEN2K8
 576/* Execute the file FD refers to, overlaying the running program image.
 577   ARGV and ENVP are passed to the new program, as for `execve'.  */
 578extern int fexecve (int __fd, char *const __argv[], char *const __envp[])
 579     __THROW __nonnull ((2));
 580#endif
 581
 582
 583/* Execute PATH with arguments ARGV and environment from `environ'.  */
 584extern int execv (const char *__path, char *const __argv[])
 585     __THROW __nonnull ((1, 2));
 586
 587/* Execute PATH with all arguments after PATH until a NULL pointer,
 588   and the argument after that for environment.  */
 589extern int execle (const char *__path, const char *__arg, ...)
 590     __THROW __nonnull ((1, 2));
 591
 592/* Execute PATH with all arguments after PATH until
 593   a NULL pointer and environment from `environ'.  */
 594extern int execl (const char *__path, const char *__arg, ...)
 595     __THROW __nonnull ((1, 2));
 596
 597/* Execute FILE, searching in the `PATH' environment variable if it contains
 598   no slashes, with arguments ARGV and environment from `environ'.  */
 599extern int execvp (const char *__file, char *const __argv[])
 600     __THROW __nonnull ((1, 2));
 601
 602/* Execute FILE, searching in the `PATH' environment variable if
 603   it contains no slashes, with all arguments after FILE until a
 604   NULL pointer and environment from `environ'.  */
 605extern int execlp (const char *__file, const char *__arg, ...)
 606     __THROW __nonnull ((1, 2));
 607
 608#ifdef __USE_GNU
 609/* Execute FILE, searching in the `PATH' environment variable if it contains
 610   no slashes, with arguments ARGV and environment from `environ'.  */
 611extern int execvpe (const char *__file, char *const __argv[],
 612		    char *const __envp[])
 613     __THROW __nonnull ((1, 2));
 614#endif
 615
 616
 617#if defined __USE_MISC || defined __USE_XOPEN
 618/* Add INC to priority of the current process.  */
 619extern int nice (int __inc) __THROW __wur;
 620#endif
 621
 622
 623/* Terminate program execution with the low-order 8 bits of STATUS.  */
 624extern void _exit (int __status) __attribute__ ((__noreturn__));
 625
 626
 627/* Get the `_PC_*' symbols for the NAME argument to `pathconf' and `fpathconf';
 628   the `_SC_*' symbols for the NAME argument to `sysconf';
 629   and the `_CS_*' symbols for the NAME argument to `confstr'.  */
 630#include <bits/confname.h>
 631
 632/* Get file-specific configuration information about PATH.  */
 633extern long int pathconf (const char *__path, int __name)
 634     __THROW __nonnull ((1));
 635
 636/* Get file-specific configuration about descriptor FD.  */
 637extern long int fpathconf (int __fd, int __name) __THROW;
 638
 639/* Get the value of the system variable NAME.  */
 640extern long int sysconf (int __name) __THROW;
 641
 642#ifdef	__USE_POSIX2
 643/* Get the value of the string-valued system variable NAME.  */
 644extern size_t confstr (int __name, char *__buf, size_t __len) __THROW
 645    __fortified_attr_access (__write_only__, 2, 3);
 646#endif
 647
 648
 649/* Get the process ID of the calling process.  */
 650extern __pid_t getpid (void) __THROW;
 651
 652/* Get the process ID of the calling process's parent.  */
 653extern __pid_t getppid (void) __THROW;
 654
 655/* Get the process group ID of the calling process.  */
 656extern __pid_t getpgrp (void) __THROW;
 657
 658/* Get the process group ID of process PID.  */
 659extern __pid_t __getpgid (__pid_t __pid) __THROW;
 660#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
 661extern __pid_t getpgid (__pid_t __pid) __THROW;
 662#endif
 663
 664
 665/* Set the process group ID of the process matching PID to PGID.
 666   If PID is zero, the current process's process group ID is set.
 667   If PGID is zero, the process ID of the process is used.  */
 668extern int setpgid (__pid_t __pid, __pid_t __pgid) __THROW;
 669
 670#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
 671/* Both System V and BSD have `setpgrp' functions, but with different
 672   calling conventions.  The BSD function is the same as POSIX.1 `setpgid'
 673   (above).  The System V function takes no arguments and puts the calling
 674   process in its on group like `setpgid (0, 0)'.
 675
 676   New programs should always use `setpgid' instead.
 677
 678   GNU provides the POSIX.1 function.  */
 679
 680/* Set the process group ID of the calling process to its own PID.
 681   This is exactly the same as `setpgid (0, 0)'.  */
 682extern int setpgrp (void) __THROW;
 683
 684#endif	/* Use misc or X/Open.  */
 685
 686/* Create a new session with the calling process as its leader.
 687   The process group IDs of the session and the calling process
 688   are set to the process ID of the calling process, which is returned.  */
 689extern __pid_t setsid (void) __THROW;
 690
 691#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
 692/* Return the session ID of the given process.  */
 693extern __pid_t getsid (__pid_t __pid) __THROW;
 694#endif
 695
 696/* Get the real user ID of the calling process.  */
 697extern __uid_t getuid (void) __THROW;
 698
 699/* Get the effective user ID of the calling process.  */
 700extern __uid_t geteuid (void) __THROW;
 701
 702/* Get the real group ID of the calling process.  */
 703extern __gid_t getgid (void) __THROW;
 704
 705/* Get the effective group ID of the calling process.  */
 706extern __gid_t getegid (void) __THROW;
 707
 708/* If SIZE is zero, return the number of supplementary groups
 709   the calling process is in.  Otherwise, fill in the group IDs
 710   of its supplementary groups in LIST and return the number written.  */
 711extern int getgroups (int __size, __gid_t __list[]) __THROW __wur
 712    __fortified_attr_access (__write_only__, 2, 1);
 713#ifdef	__USE_GNU
 714/* Return nonzero iff the calling process is in group GID.  */
 715extern int group_member (__gid_t __gid) __THROW;
 716#endif
 717
 718/* Set the user ID of the calling process to UID.
 719   If the calling process is the super-user, set the real
 720   and effective user IDs, and the saved set-user-ID to UID;
 721   if not, the effective user ID is set to UID.  */
 722extern int setuid (__uid_t __uid) __THROW __wur;
 723
 724#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
 725/* Set the real user ID of the calling process to RUID,
 726   and the effective user ID of the calling process to EUID.  */
 727extern int setreuid (__uid_t __ruid, __uid_t __euid) __THROW __wur;
 728#endif
 729
 730#ifdef __USE_XOPEN2K
 731/* Set the effective user ID of the calling process to UID.  */
 732extern int seteuid (__uid_t __uid) __THROW __wur;
 733#endif /* Use POSIX.1-2001.  */
 734
 735/* Set the group ID of the calling process to GID.
 736   If the calling process is the super-user, set the real
 737   and effective group IDs, and the saved set-group-ID to GID;
 738   if not, the effective group ID is set to GID.  */
 739extern int setgid (__gid_t __gid) __THROW __wur;
 740
 741#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
 742/* Set the real group ID of the calling process to RGID,
 743   and the effective group ID of the calling process to EGID.  */
 744extern int setregid (__gid_t __rgid, __gid_t __egid) __THROW __wur;
 745#endif
 746
 747#ifdef __USE_XOPEN2K
 748/* Set the effective group ID of the calling process to GID.  */
 749extern int setegid (__gid_t __gid) __THROW __wur;
 750#endif /* Use POSIX.1-2001.  */
 751
 752#ifdef __USE_GNU
 753/* Fetch the real user ID, effective user ID, and saved-set user ID,
 754   of the calling process.  */
 755extern int getresuid (__uid_t *__ruid, __uid_t *__euid, __uid_t *__suid)
 756     __THROW;
 757
 758/* Fetch the real group ID, effective group ID, and saved-set group ID,
 759   of the calling process.  */
 760extern int getresgid (__gid_t *__rgid, __gid_t *__egid, __gid_t *__sgid)
 761     __THROW;
 762
 763/* Set the real user ID, effective user ID, and saved-set user ID,
 764   of the calling process to RUID, EUID, and SUID, respectively.  */
 765extern int setresuid (__uid_t __ruid, __uid_t __euid, __uid_t __suid)
 766     __THROW __wur;
 767
 768/* Set the real group ID, effective group ID, and saved-set group ID,
 769   of the calling process to RGID, EGID, and SGID, respectively.  */
 770extern int setresgid (__gid_t __rgid, __gid_t __egid, __gid_t __sgid)
 771     __THROW __wur;
 772#endif
 773
 774
 775/* Clone the calling process, creating an exact copy.
 776   Return -1 for errors, 0 to the new process,
 777   and the process ID of the new process to the old process.  */
 778extern __pid_t fork (void) __THROWNL;
 779
 780#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8) \
 781    || defined __USE_MISC
 782/* Clone the calling process, but without copying the whole address space.
 783   The calling process is suspended until the new process exits or is
 784   replaced by a call to `execve'.  Return -1 for errors, 0 to the new process,
 785   and the process ID of the new process to the old process.  */
 786extern __pid_t vfork (void) __THROW;
 787#endif /* Use misc or XPG < 7. */
 788
 789#ifdef __USE_GNU
 790/* This is similar to fork, however it does not run the atfork handlers
 791   neither reinitialize any internal locks in multithread case.
 792   Different than fork, _Fork is async-signal-safe.  */
 793extern __pid_t _Fork (void) __THROW;
 794#endif
 795
 796
 797/* Return the pathname of the terminal FD is open on, or NULL on errors.
 798   The returned storage is good only until the next call to this function.  */
 799extern char *ttyname (int __fd) __THROW;
 800
 801/* Store at most BUFLEN characters of the pathname of the terminal FD is
 802   open on in BUF.  Return 0 on success, otherwise an error number.  */
 803extern int ttyname_r (int __fd, char *__buf, size_t __buflen)
 804     __THROW __nonnull ((2)) __wur
 805     __fortified_attr_access (__write_only__, 2, 3);
 806
 807/* Return 1 if FD is a valid descriptor associated
 808   with a terminal, zero if not.  */
 809extern int isatty (int __fd) __THROW;
 810
 811#ifdef __USE_MISC
 812/* Return the index into the active-logins file (utmp) for
 813   the controlling terminal.  */
 814extern int ttyslot (void) __THROW;
 815#endif
 816
 817
 818/* Make a link to FROM named TO.  */
 819extern int link (const char *__from, const char *__to)
 820     __THROW __nonnull ((1, 2)) __wur;
 821
 822#ifdef __USE_ATFILE
 823/* Like link but relative paths in TO and FROM are interpreted relative
 824   to FROMFD and TOFD respectively.  */
 825extern int linkat (int __fromfd, const char *__from, int __tofd,
 826		   const char *__to, int __flags)
 827     __THROW __nonnull ((2, 4)) __wur;
 828#endif
 829
 830#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
 831/* Make a symbolic link to FROM named TO.  */
 832extern int symlink (const char *__from, const char *__to)
 833     __THROW __nonnull ((1, 2)) __wur;
 834
 835/* Read the contents of the symbolic link PATH into no more than
 836   LEN bytes of BUF.  The contents are not null-terminated.
 837   Returns the number of characters read, or -1 for errors.  */
 838extern ssize_t readlink (const char *__restrict __path,
 839			 char *__restrict __buf, size_t __len)
 840     __THROW __nonnull ((1, 2)) __wur
 841     __fortified_attr_access (__write_only__, 2, 3);
 842
 843#endif /* Use POSIX.1-2001.  */
 844
 845#ifdef __USE_ATFILE
 846/* Like symlink but a relative path in TO is interpreted relative to TOFD.  */
 847extern int symlinkat (const char *__from, int __tofd,
 848		      const char *__to) __THROW __nonnull ((1, 3)) __wur;
 849
 850/* Like readlink but a relative PATH is interpreted relative to FD.  */
 851extern ssize_t readlinkat (int __fd, const char *__restrict __path,
 852			   char *__restrict __buf, size_t __len)
 853     __THROW __nonnull ((2, 3)) __wur
 854     __fortified_attr_access (__write_only__, 3, 4);
 855#endif
 856
 857/* Remove the link NAME.  */
 858extern int unlink (const char *__name) __THROW __nonnull ((1));
 859
 860#ifdef __USE_ATFILE
 861/* Remove the link NAME relative to FD.  */
 862extern int unlinkat (int __fd, const char *__name, int __flag)
 863     __THROW __nonnull ((2));
 864#endif
 865
 866/* Remove the directory PATH.  */
 867extern int rmdir (const char *__path) __THROW __nonnull ((1));
 868
 869
 870/* Return the foreground process group ID of FD.  */
 871extern __pid_t tcgetpgrp (int __fd) __THROW;
 872
 873/* Set the foreground process group ID of FD set PGRP_ID.  */
 874extern int tcsetpgrp (int __fd, __pid_t __pgrp_id) __THROW;
 875
 876
 877/* Return the login name of the user.
 878
 879   This function is a possible cancellation point and therefore not
 880   marked with __THROW.  */
 881extern char *getlogin (void);
 882#ifdef __USE_POSIX199506
 883/* Return at most NAME_LEN characters of the login name of the user in NAME.
 884   If it cannot be determined or some other error occurred, return the error
 885   code.  Otherwise return 0.
 886
 887   This function is a possible cancellation point and therefore not
 888   marked with __THROW.  */
 889extern int getlogin_r (char *__name, size_t __name_len) __nonnull ((1))
 890    __fortified_attr_access (__write_only__, 1, 2);
 891#endif
 892
 893#ifdef	__USE_MISC
 894/* Set the login name returned by `getlogin'.  */
 895extern int setlogin (const char *__name) __THROW __nonnull ((1));
 896#endif
 897
 898
 899#ifdef	__USE_POSIX2
 900/* Get definitions and prototypes for functions to process the
 901   arguments in ARGV (ARGC of them, minus the program name) for
 902   options given in OPTS.  */
 903# include <bits/getopt_posix.h>
 904#endif
 905
 906
 907#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
 908/* Put the name of the current host in no more than LEN bytes of NAME.
 909   The result is null-terminated if LEN is large enough for the full
 910   name and the terminator.  */
 911extern int gethostname (char *__name, size_t __len) __THROW __nonnull ((1))
 912    __fortified_attr_access (__write_only__, 1, 2);
 913#endif
 914
 915
 916#if defined __USE_MISC
 917/* Set the name of the current host to NAME, which is LEN bytes long.
 918   This call is restricted to the super-user.  */
 919extern int sethostname (const char *__name, size_t __len)
 920     __THROW __nonnull ((1)) __wur __attr_access ((__read_only__, 1, 2));
 921
 922/* Set the current machine's Internet number to ID.
 923   This call is restricted to the super-user.  */
 924extern int sethostid (long int __id) __THROW __wur;
 925
 926
 927/* Get and set the NIS (aka YP) domain name, if any.
 928   Called just like `gethostname' and `sethostname'.
 929   The NIS domain name is usually the empty string when not using NIS.  */
 930extern int getdomainname (char *__name, size_t __len)
 931     __THROW __nonnull ((1)) __wur
 932     __fortified_attr_access (__write_only__, 1, 2);
 933extern int setdomainname (const char *__name, size_t __len)
 934     __THROW __nonnull ((1)) __wur __attr_access ((__read_only__, 1, 2));
 935
 936/* Revoke access permissions to all processes currently communicating
 937   with the control terminal, and then send a SIGHUP signal to the process
 938   group of the control terminal.  */
 939extern int vhangup (void) __THROW;
 940
 941/* Revoke the access of all descriptors currently open on FILE.  */
 942extern int revoke (const char *__file) __THROW __nonnull ((1)) __wur;
 943
 944
 945/* Enable statistical profiling, writing samples of the PC into at most
 946   SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
 947   is enabled, the system examines the user PC and increments
 948   SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536].  If SCALE is zero,
 949   disable profiling.  Returns zero on success, -1 on error.  */
 950extern int profil (unsigned short int *__sample_buffer, size_t __size,
 951		   size_t __offset, unsigned int __scale)
 952     __THROW __nonnull ((1));
 953
 954
 955/* Turn accounting on if NAME is an existing file.  The system will then write
 956   a record for each process as it terminates, to this file.  If NAME is NULL,
 957   turn accounting off.  This call is restricted to the super-user.  */
 958extern int acct (const char *__name) __THROW;
 959
 960
 961/* Successive calls return the shells listed in `/etc/shells'.  */
 962extern char *getusershell (void) __THROW;
 963extern void endusershell (void) __THROW; /* Discard cached info.  */
 964extern void setusershell (void) __THROW; /* Rewind and re-read the file.  */
 965
 966
 967/* Put the program in the background, and dissociate from the controlling
 968   terminal.  If NOCHDIR is zero, do `chdir ("/")'.  If NOCLOSE is zero,
 969   redirects stdin, stdout, and stderr to /dev/null.  */
 970extern int daemon (int __nochdir, int __noclose) __THROW __wur;
 971#endif /* Use misc.  */
 972
 973
 974#if defined __USE_MISC || (defined __USE_XOPEN && !defined __USE_XOPEN2K)
 975/* Make PATH be the root directory (the starting point for absolute paths).
 976   This call is restricted to the super-user.  */
 977extern int chroot (const char *__path) __THROW __nonnull ((1)) __wur;
 978
 979/* Prompt with PROMPT and read a string from the terminal without echoing.
 980   Uses /dev/tty if possible; otherwise stderr and stdin.  */
 981extern char *getpass (const char *__prompt) __nonnull ((1));
 982#endif /* Use misc || X/Open.  */
 983
 984
 985/* Make all changes done to FD actually appear on disk.
 986
 987   This function is a cancellation point and therefore not marked with
 988   __THROW.  */
 989extern int fsync (int __fd);
 990
 991
 992#ifdef __USE_GNU
 993/* Make all changes done to all files on the file system associated
 994   with FD actually appear on disk.  */
 995extern int syncfs (int __fd) __THROW;
 996#endif
 997
 998
 999#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
1000
1001/* Return identifier for the current host.  */
1002extern long int gethostid (void);
1003
1004/* Make all changes done to all files actually appear on disk.  */
1005extern void sync (void) __THROW;
1006
1007
1008# if defined __USE_MISC || !defined __USE_XOPEN2K
1009/* Return the number of bytes in a page.  This is the system's page size,
1010   which is not necessarily the same as the hardware page size.  */
1011extern int getpagesize (void)  __THROW __attribute__ ((__const__));
1012
1013
1014/* Return the maximum number of file descriptors
1015   the current process could possibly have.  */
1016extern int getdtablesize (void) __THROW;
1017# endif
1018
1019#endif /* Use misc || X/Open Unix.  */
1020
1021
1022#if defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K8
1023
1024/* Truncate FILE to LENGTH bytes.  */
1025# ifndef __USE_FILE_OFFSET64
1026extern int truncate (const char *__file, __off_t __length)
1027     __THROW __nonnull ((1)) __wur;
1028# else
1029#  ifdef __REDIRECT_NTH
1030extern int __REDIRECT_NTH (truncate,
1031			   (const char *__file, __off64_t __length),
1032			   truncate64) __nonnull ((1)) __wur;
1033#  else
1034#   define truncate truncate64
1035#  endif
1036# endif
1037# ifdef __USE_LARGEFILE64
1038extern int truncate64 (const char *__file, __off64_t __length)
1039     __THROW __nonnull ((1)) __wur;
1040# endif
1041
1042#endif /* Use X/Open Unix || POSIX 2008.  */
1043
1044#if defined __USE_POSIX199309 \
1045    || defined __USE_XOPEN_EXTENDED || defined __USE_XOPEN2K
1046
1047/* Truncate the file FD is open on to LENGTH bytes.  */
1048# ifndef __USE_FILE_OFFSET64
1049extern int ftruncate (int __fd, __off_t __length) __THROW __wur;
1050# else
1051#  ifdef __REDIRECT_NTH
1052extern int __REDIRECT_NTH (ftruncate, (int __fd, __off64_t __length),
1053			   ftruncate64) __wur;
1054#  else
1055#   define ftruncate ftruncate64
1056#  endif
1057# endif
1058# ifdef __USE_LARGEFILE64
1059extern int ftruncate64 (int __fd, __off64_t __length) __THROW __wur;
1060# endif
1061
1062#endif /* Use POSIX.1b || X/Open Unix || XPG6.  */
1063
1064
1065#if (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K) \
1066    || defined __USE_MISC
1067
1068/* Set the end of accessible data space (aka "the break") to ADDR.
1069   Returns zero on success and -1 for errors (with errno set).  */
1070extern int brk (void *__addr) __THROW __wur;
1071
1072/* Increase or decrease the end of accessible data space by DELTA bytes.
1073   If successful, returns the address the previous end of data space
1074   (i.e. the beginning of the new space, if DELTA > 0);
1075   returns (void *) -1 for errors (with errno set).  */
1076extern void *sbrk (intptr_t __delta) __THROW;
1077#endif
1078
1079
1080#ifdef __USE_MISC
1081/* Invoke `system call' number SYSNO, passing it the remaining arguments.
1082   This is completely system-dependent, and not often useful.
1083
1084   In Unix, `syscall' sets `errno' for all errors and most calls return -1
1085   for errors; in many systems you cannot pass arguments or get return
1086   values for all system calls (`pipe', `fork', and `getppid' typically
1087   among them).
1088
1089   In Mach, all system calls take normal arguments and always return an
1090   error code (zero for success).  */
1091extern long int syscall (long int __sysno, ...) __THROW;
1092
1093#endif	/* Use misc.  */
1094
1095
1096#if (defined __USE_MISC || defined __USE_XOPEN_EXTENDED) && !defined F_LOCK
1097/* NOTE: These declarations also appear in <fcntl.h>; be sure to keep both
1098   files consistent.  Some systems have them there and some here, and some
1099   software depends on the macros being defined without including both.  */
1100
1101/* `lockf' is a simpler interface to the locking facilities of `fcntl'.
1102   LEN is always relative to the current file position.
1103   The CMD argument is one of the following.
1104
1105   This function is a cancellation point and therefore not marked with
1106   __THROW.  */
1107
1108# define F_ULOCK 0	/* Unlock a previously locked region.  */
1109# define F_LOCK  1	/* Lock a region for exclusive use.  */
1110# define F_TLOCK 2	/* Test and lock a region for exclusive use.  */
1111# define F_TEST  3	/* Test a region for other processes locks.  */
1112
1113# ifndef __USE_FILE_OFFSET64
1114extern int lockf (int __fd, int __cmd, __off_t __len) __wur;
1115# else
1116#  ifdef __REDIRECT
1117extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len),
1118		       lockf64) __wur;
1119#  else
1120#   define lockf lockf64
1121#  endif
1122# endif
1123# ifdef __USE_LARGEFILE64
1124extern int lockf64 (int __fd, int __cmd, __off64_t __len) __wur;
1125# endif
1126#endif /* Use misc and F_LOCK not already defined.  */
1127
1128
1129#ifdef __USE_GNU
1130
1131/* Evaluate EXPRESSION, and repeat as long as it returns -1 with `errno'
1132   set to EINTR.  */
1133
1134# define TEMP_FAILURE_RETRY(expression) \
1135  (__extension__							      \
1136    ({ long int __result;						      \
1137       do __result = (long int) (expression);				      \
1138       while (__result == -1L && errno == EINTR);			      \
1139       __result; }))
1140
1141// zig patch: copy_file_range was added in glibc 2.27
1142#if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 27) || __GLIBC__ > 2
1143
1144/* Copy LENGTH bytes from INFD to OUTFD.  */
1145ssize_t copy_file_range (int __infd, __off64_t *__pinoff,
1146			 int __outfd, __off64_t *__poutoff,
1147			 size_t __length, unsigned int __flags);
1148
1149#endif /* glibc 2.27 or later */
1150
1151#endif /* __USE_GNU */
1152
1153#if defined __USE_POSIX199309 || defined __USE_UNIX98
1154/* Synchronize at least the data part of a file with the underlying
1155   media.  */
1156extern int fdatasync (int __fildes);
1157#endif /* Use POSIX199309 */
1158
1159#ifdef __USE_MISC
1160/* One-way hash PHRASE, returning a string suitable for storage in the
1161   user database.  SALT selects the one-way function to use, and
1162   ensures that no two users' hashes are the same, even if they use
1163   the same passphrase.  The return value points to static storage
1164   which will be overwritten by the next call to crypt.
1165
1166   This declaration is deprecated; applications should include
1167   <crypt.h> instead.  */
1168extern char *crypt (const char *__key, const char *__salt)
1169     __THROW __nonnull ((1, 2));
1170#endif
1171
1172#ifdef	__USE_XOPEN
1173/* Swab pairs bytes in the first N bytes of the area pointed to by
1174   FROM and copy the result to TO.  The value of TO must not be in the
1175   range [FROM - N + 1, FROM - 1].  If N is odd the first byte in FROM
1176   is without partner.  */
1177extern void swab (const void *__restrict __from, void *__restrict __to,
1178		  ssize_t __n) __THROW __nonnull ((1, 2))
1179    __attr_access ((__read_only__, 1, 3))
1180    __attr_access ((__write_only__, 2, 3));
1181#endif
1182
1183
1184/* Prior to Issue 6, the Single Unix Specification required these
1185   prototypes to appear in this header.  They are also found in
1186   <stdio.h>.  */
1187#if defined __USE_XOPEN && !defined __USE_XOPEN2K
1188/* Return the name of the controlling terminal.  */
1189extern char *ctermid (char *__s) __THROW;
1190
1191/* Return the name of the current user.  */
1192extern char *cuserid (char *__s);
1193#endif
1194
1195
1196/* Unix98 requires this function to be declared here.  In other
1197   standards it is in <pthread.h>.  */
1198#if defined __USE_UNIX98 && !defined __USE_XOPEN2K
1199extern int pthread_atfork (void (*__prepare) (void),
1200			   void (*__parent) (void),
1201			   void (*__child) (void)) __THROW;
1202#endif
1203
1204#ifdef __USE_MISC
1205/* Write LENGTH bytes of randomness starting at BUFFER.  Return 0 on
1206   success or -1 on error.  */
1207int getentropy (void *__buffer, size_t __length) __wur
1208    __attr_access ((__write_only__, 1, 2));
1209#endif
1210
1211#ifdef __USE_GNU
1212// zig patch: check target glibc version
1213# if (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 34) || __GLIBC__ > 2
1214/* Close all file descriptors in the range FD up to MAX_FD.  The flag FLAGS
1215   are define by the CLOSE_RANGE prefix.  This function behaves like close
1216   on the range and gaps where the file descriptor is invalid or errors
1217   encountered while closing file descriptors are ignored.   Returns 0 on
1218   successor or -1 for failure (and sets errno accordingly).  */
1219extern int close_range (unsigned int __fd, unsigned int __max_fd,
1220			int __flags) __THROW;
1221# endif
1222#endif
1223
1224/* Define some macros helping to catch buffer overflows.  */
1225#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function
1226# include <bits/unistd.h>
1227#endif
1228
1229/* System-specific extensions.  */
1230#include <bits/unistd_ext.h>
1231
1232__END_DECLS
1233
1234#endif /* unistd.h  */