/**
* slibc — Yet another C library
* Copyright © 2015 Mattias Andrée (maandree@member.fsf.org)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _UNISTD_H
#define _UNISTD_H
#include <slibc/version.h>
#include <slibc/features.h>
#define __NEED_size_t
#define __NEED_ssize_t
#define __NEED_uid_t
#define __NEED_gid_t
#define __NEED_off_t
#define __NEED_pid_t
#define __NEED_ptrdiff_t
#define __NEED_intptr_t
#define __NEED_useconds_t
#include <bits/types.h>
/**
* `NULL`'s canonical header is <stddef.h>.
*/
#ifndef NULL
# define NULL ((void*)0)
#endif
/**
* The file descriptor for stdin.
* The file with input.
*
* @etymology (St)andar(d) (in)put (file)descriptor (number).
*
* @since Always.
*/
#define STDIN_FILENO 0
/**
* The file descriptor for stdout.
* The file for output.
*
* @etymology (St)andar(d) (out)put (file)descriptor (number).
*
* @since Always.
*/
#define STDOUT_FILENO 1
/**
* The file descriptor for stderr.
* The file for error messages and warnings.
*
* @etymology (St)andar(d) (err)or output (file)descriptor (number).
*
* @since Always.
*/
#define STDERR_FILENO 2
/**
* Used in `access` and `faccessat`, to check
* weather a file appears to exists for the
* current user. It is impled for `X_OK`,
* `W_OK` and `R_OK`.
*
* Its value, 0, comes from that this check
* is always performed.
*
* @etymology This constant is named in symmetry with
* `X_OK`, `W_OK`, and `R_OK`. The 'F' comes
* from "(f)ile exists", and '_OK' comes
* from the name of the other '?(_OK)'
* constants.
*
* @since Always.
*/
#define F_OK 0
/**
* Used in `access` and `faccessat`, to check
* weather a file is executable (for directories:
* its content can be listed) for the current
* user. Implies `F_OK`.
*
* Its value, 1, comes from that for each user-octet
* in the permission bits, the bit 1 signifies that
* the file is executable.
*
* @etymology Is e(x)ecute (ok)ay?
*
* @since Always.
*/
#define X_OK 1
/**
* Used in `access` and `faccessat`, to check
* weather a file is writable for the current
* user. Implies `F_OK`.
*
* Its value, 2, comes from that for each user-octet
* in the permission bits, the bit 2 signifies that
* the file is writable.
*
* @since Always.
* @etymology Is (w)rite (ok)ay?
*/
#define W_OK 2
/**
* Used in `access` and `faccessat`, to check
* weather a file is readable for the current
* user. Implies `F_OK`.
*
* Its value, 4, comes from that for each user-octet
* in the permission bits, the bit 4 signifies that
* the file is readable.
*
* @etymology Is (r)ead (ok)ay?
*
* @since Always.
*/
#define R_OK 4
/**
* Set the high end of the calling process's
* data segment.
*
* The high end is defined as the last byte
* in the segment plus 1.
*
* Using `brk` is highly discouraged. `malloc`,
* `calloc` and `free`, and its related functions,
* fall be used instead as they are much more
* conformable. Use of `brk` can couse errors
* when using `malloc`, `free`, &c. Thus, `brk`
* shall (bascially) only be used if you are
* writting an alterantive malloc-implementation.
*
* `brk` was marked LEGACY in SUSv2, and it
* was removed from the POSIX standard in revision
* POSIX.1-2001. It is however fundamental in
* implementing a fast `malloc`-implementation.
*
* @etymology Set (br)ea(k).
*
* @param address The process's new high end of its data segment.
* If lower than the current low end, nothing will
* happen and the function will return with a success
* status.
* @return Zero on succes, -1 on error. On error, `errno`
* is set to indicate the error.
*
* @throws ENOMEM The process can allocate the requested amount
* of memory. Either the process store limit would
* have been exceeded, RAM and swap memory would
* have been exhausted, or the request would cause
* the data segment to overlap another segment.
*
* @since Always.
*/
int brk(void*) /* TODO implement brk */
__GCC_ONLY(__attribute__((__warn_unused_result__)));
/**
* Set and get the current high end of the calling
* process's data segment.
*
* There is some documents that state that the new,
* rather than the previous, high end is returned.
* Additionally, some documentions do not document
* possible failure. Thus only `sbrk(0)` is guaranteed
* to be portable. The return type differs between
* implementations; common return types are `int`,
* `ssize_t`, `ptrdiff_t`, `ptrdiff_t`, `intptr_t`,
* and `void*`. Note that `int` is
* microarchitecture-portable.
*
* `sbrk` was marked LEGACY in SUSv2, and it
* was removed from the POSIX standard in revision
* POSIX.1-2001. It is however fundamental in
* implementing a fast `malloc`-implementation.
*
* @etymology Shift (br)ea(k).
*
* @param delta The incremant of the size of the data segment,
* zero means that the high end shall not be moved
* (thus the current high end is returned,) a
* positive value will cause the segment to grow,
* a negative value will cause the segment to shrink.
* @return The previous high end. `(void*)-1` is returned on error.
*
* @throws ENOMEM The process can allocate the requested amount
* of memory. Either the process store limit would
* have been exceeded, RAM and swap memory would
* have been exhausted, or the request would cause
* the data segment to overlap another segment.
*
* @since Always.
*/
void* sbrk(ptrdiff_t) /* TODO implement sbrk */
__GCC_ONLY(__attribute__((__warn_unused_result__)));
/* TODO implement exit-functions */
__noreturn void _exit(int);
/* TODO implement I/O */
int isatty(int);
/**
* Replace the current process image with a new process image.
*
* @param path The pathname of the file to execute.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execl(const char*, ... /*, NULL */)
__GCC_ONLY(__attribute__((__sentinel__(0), __nonnull__(1))));
/**
* Replace the current process image with a new process image.
*
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execlp(const char*, ... /*, NULL */)
__GCC_ONLY(__attribute__((__sentinel__(0), __nonnull__(1))));
/**
* Replace the current process image with a new process image.
*
* @param path The pathname of the file to execute.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execle(const char*, ... /*, NULL, char* const[] */)
__GCC_ONLY(__attribute__((__sentinel__(1), __nonnull__(1))));
#if defined(__SLIBC_SOURCE)
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension, added for completeness.
*
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execlpe(const char*, ... /*, NULL, char* const[] */)
__GCC_ONLY(__attribute__((__sentinel__(1), __nonnull__(1))));
#endif
/**
* Replace the current process image with a new process image.
*
* @param path The pathname of the file to execute.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execv(const char*, char* const[])
__GCC_ONLY(__attribute__((__nonnull__(1))));
/**
* Replace the current process image with a new process image.
*
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execvp(const char*, char* const[])
__GCC_ONLY(__attribute__((__nonnull__(1))));
/**
* Replace the current process image with a new process image.
*
* @param path The pathname of the file to execute.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execve(const char*, char* const[], char* const[])
__GCC_ONLY(__attribute__((__nonnull__(1))));
#if defined(__GNU_SOURCE) || defined(__SLIBC_SOURCE)
/**
* Replace the current process image with a new process image.
*
* This is a GNU-compliant slibc extension.
*
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int execvpe(const char*, char* const[], char* const[])
__GCC_ONLY(__attribute__((__nonnull__(1))));
#endif
#if defined(__SLIBC_SOURCE)
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param path The pathname of the file to execute.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `path` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `path` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execlat(int, const char*, ... /*, NULL, int */)
__GCC_ONLY(__attribute__((__sentinel__(1), __nonnull__(2))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `file` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `file` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execlpat(int, const char*, ... /*, NULL, int */)
__GCC_ONLY(__attribute__((__sentinel__(1), __nonnull__(2))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param path The pathname of the file to execute.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `path` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `path` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execleat(int, const char*, ... /*, NULL, char* const[], int */)
__GCC_ONLY(__attribute__((__sentinel__(2), __nonnull__(2))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `file` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `file` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execlpeat(int, const char*, ... /*, NULL, char* const[], int */)
__GCC_ONLY(__attribute__((__sentinel__(2), __nonnull__(2))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param path The pathname of the file to execute.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `path` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `path` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execvat(int, const char*, char* const[], int)
__GCC_ONLY(__attribute__((__nonnull__(2))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `file` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `file` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execvpat(int, const char*, char* const[], int)
__GCC_ONLY(__attribute__((__nonnull__(2))));
#endif
/**
* Replace the current process image with a new process image.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param path The pathname of the file to execute.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `path` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `path` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execveat(int, const char*, char* const[], char* const[], int)
__GCC_ONLY(__attribute__((__nonnull__(2))));
#if defined(__SLIBC_SOURCE)
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param dirfd File descriptor for a directory (opened with
* with the open(2) `O_PATH` flag,) that will
* act as the current working directory.
* If `AT_FDCWD`, the current working directory
* will be used.
* @param file The pathname of the file to execute,
* or the filename of a file in $PATH,
* to execute. If $PATH is not set, the current
* working directory (yes, you read that right,)
* and a default value for $PATH will be used.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @param flags Bit mask that can include zero or more of the
* following flags:
* AT_EMPTY_PATH:
* If `file` is an empty string, operate on the
* file (not directory) referred to by `dirfd`.
* AT_SYMLINK_NOFOLLOW:
* If `file` is relative is a symbolic link,
* fail with `errno` set to `ELOOP`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execveat(2).
*
* @since Always.
*/
int execvpeat(int, const char*, char* const[], char* const[], int)
__GCC_ONLY(__attribute__((__nonnull__(2))));
#endif
#if defined(__SLIBC_SOURCE)
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param fd File descriptor for the file to execute.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int fexecl(int, ... /*, NULL */)
__GCC_ONLY(__attribute__((__sentinel__(0))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param fd File descriptor for the file to execute.
* @param ... The arguments with which to execute the file.
* The arguments should have the type `const char*`.
* As a slibc extension, it can be empty.
* This list shall be terminated by a `NULL` sentinel.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int fexecle(int, ... /*, NULL, char* const[] */)
__GCC_ONLY(__attribute__((__sentinel__(1))));
/**
* Replace the current process image with a new process image.
*
* This is a slibc extension.
*
* @param fd File descriptor for the file to execute.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int fexecv(int, char* const[]);
#endif
/**
* Replace the current process image with a new process image.
*
* @param fd File descriptor for the file to execute.
* @param argv The arguments with which to execute the file.
* This parameter should really have the type
* `const char* const[]`, but that probably not
* so because compiles take issue with casts
* adding const to any pointer in the type
* except the outmost pointer. This list shall
* be `NULL`-terminated. The behaviour is
* system-dependant if this argument is `NULL`.
* @param envp The list of environment variables the new program shall
* have set. Each element shall be formatted $name=$value.
* This list shall be `NULL`-terminated. The behaviour
* is system-dependant if this argument is `NULL`.
* @return This function does not return on success,
* on error, -1 is returned and `errno` is
* set to describe the error.
*
* @throws Any error specified for execve(2).
*
* @since Always.
*/
int fexecve(int, char* const[], char* const[]);
#if defined(__PLAN9_SOURCE) || defined(__SLIBC_SOURCE)
/**
* Search the environment variable $PATH for an executable
* file whose name is the specified name. Slashes are ignored
* and treated as any other character. $PATH is searched
* for left to right, and ':' is used as the path-delimiter.
*
* $PATH is not inspected if `name` starts with './', '../', or '/'.
*
* This is a Plan 9 from Bell Labs compliant slibc extension.
*
* @etymology (Search) ($PATH) for an executable.
*
* @param name The name of the sought executable. Must not be `NULL`.
* @return The pathname of the sought file, `NULL` on error,
* or if not found. Files that are not executable
* are (almost) ignored.
*
* @throws ENOMEM The process cannot allocate enough memory.
* @throws ENOENT $PATH is not defined, there are no directories
* listed in $PATH, or the sought file is not
* exist inside $PATH.
* @throws EACCES None of the candidates (with at least one candidate)
* are executable by the current user.
* @throws Any exception defined for access(3), except for `EROFS`,
* these when encountered, the search is aborted, unless
* the error is `ENOENT` or `EACCES`.
*
* @since Always.
*/
char* searchpath(const char*)
__GCC_ONLY(__attribute__((__nonnull__(1), __warn_unused_result__)));
#endif
#if defined(__SLIBC_SOURCE)
/**
* Search the environment variable $PATH for an executable
* file whose name is the specified name. Slashes are ignored
* and treated as any other character. $PATH is searched
* for left to right, and ':' is used as the path-delimiter.
* If $PATH is not defined, a fallback value for $PATH will be
* used.
*
* $PATH is not inspected if `name` starts with './', '../', or '/'.
*
* This function was added because it was useful in implementing
* the `exec`-function family.
*
* This is a slibc extension.
*
* @etymology Variant of (searchpath) that takes (2) arguments.
*
* @param name The name of the sought executable. Must not be `NULL`.
* @param fallback Value to use instead of the value of $PATH, if
* path is not defined. If `NULL` the default value
* for $PATH is used.
* @return The pathname of the sought file, `NULL` on error,
* or if not found. Files that are not executable
* are (almost) ignored.
*
* @throws ENOMEM The process cannot allocate enough memory.
* @throws ENOENT There are no directories listed in $PATH, or
* the sought file is not exist inside $PATH.
* @throws EACCES None of the candidates (with at least one candidate)
* are executable by the current user.
* @throws Any exception defined for access(3), except for `EROFS`,
* these when encountered, the search is aborted, unless
* the error is `ENOENT` or `EACCES`.
*
* @since Always.
*/
char* searchpath2(const char*, const char*)
__GCC_ONLY(__attribute__((__nonnull__(1), __warn_unused_result__)));
/**
* Search the environment variable $PATH for an executable
* file whose name is the specified name. Slashes are ignored
* and treated as any other character. $PATH is searched
* for left to right, and ':' is used as the path-delimiter.
* If $PATH is not defined, a fallback value for $PATH will be
* used.
*
* $PATH is not inspected if `name` starts with './', '../', or '/'.
*
* This function was added because it was useful in implementing
* the `exec`-function family.
*
* This is a slibc extension.
*
* @etymology Variant of (searchpath) that takes (2) arguments.
*
* @param name The name of the sought executable. Must not be `NULL`.
* @param fallback Value to use instead of the value of $PATH, if
* path is not defined. If `NULL` the default value
* for $PATH is used.
* @param first If $PATH is not defined, and `fallback` is `NULL`,
* these directories are tested before the default
* directories. May be `NULL`.
* @return The pathname of the sought file, `NULL` on error,
* or if not found. Files that are not executable
* are (almost) ignored.
*
* @throws ENOMEM The process cannot allocate enough memory.
* @throws ENOENT There are no directories listed in $PATH, or
* the sought file is not exist inside $PATH.
* @throws EACCES None of the candidates (with at least one candidate)
* are executable by the current user.
* @throws Any exception defined for access(3), except for `EROFS`,
* these when encountered, the search is aborted, unless
* the error is `ENOENT` or `EACCES`.
*
* @since Always.
*/
char* searchpath3(const char*, const char*, const char*)
__GCC_ONLY(__attribute__((__nonnull__(1), __warn_unused_result__)));
#endif
#if defined(__BSD_SOURCE) || defined(__XOPEN_SOURCE)
/**
* Detach the process from the controlling terminal
* and run in the background.
*
* The function shall change the working directory
* to '/' to avoid block a mountpoint from being
* unmounted. It shall also change direct stdin,
* stdout, and stderr to '/dev/null'. It shall
* then double-fork, and between the fork, become
* a session leader, temporarily, so that the
* it no longer has a controlling terminal.
*
* Note well, this function does not implement a
* reliable or particularly correct mechanism for
* daemonising a process. It shall not be used!
* Note, the GNU implementation is slightly
* different because of a bug.
*
* @etymology (Daemon)ise!
*
* @param nochdir The not change working directory to '/'.
* @param noclose The not redirect stdin, stdout, and stderr to '/dev/null'.
* @return Zero on success, -1 on error.
*
* @throws EACCES If `nochdir` is zero, and the user is denied access to '/'.
* @throws Any error specified for open(3).
* @throws Any error specified for dup2(3).
* @throws Any error specified for fork(3).
* @throws Any error specified for setsid(3).
*
* @since Always.
*/
int daemon(int, int)
__deprecated("Portable programs should implement this mechanism "
"manually. Non-portable programs may use 'daemonise'.");
#endif
#if defined(__SLIBC_SOURCE)
/**
* Leave all opened files open.
*/
#define DAEMONISE_NO_CLOSE 1
/**
* Leave all signal handlers rather than
* appling default signal handlers.
*/
#define DAEMONISE_NO_SIG_DFL 2
/**
* Leave the signal block mask as-is.
*/
#define DAEMONISE_KEEP_SIGMASK 4
/**
* Do not remove malformatted environment entries.
*/
#define DAEMONISE_KEEP_ENVIRON 8
/**
* Do not set umask to zero.
*/
#define DAEMONISE_KEEP_UMASK 16
/**
* Do not create a PID file.
*/
#define DAEMONISE_NO_PID_FILE 32
/**
* Do not close stderr even if it is
* a terminal device.
*
* Cannot be combined with `DAEMONISE_KEEP_STDERR`.
*/
#define DAEMONISE_KEEP_STDERR 64
/**
* Close stderr even if it is
* not a terminal device.
*
* Cannot be combined with `DAEMONISE_KEEP_STDERR`.
*/
#define DAEMONISE_CLOSE_STDERR 128
/**
* Do not close stdin.
*/
#define DAEMONISE_KEEP_STDIN 256
/**
* Do not close stdout.
*/
#define DAEMONISE_KEEP_STDOUT 512
/**
* Daemonise the process. This means to:
*
* - close all file descritors except for those to
* stdin, stdout, and stderr,
*
* - remove all custom signal handlers, and apply
* the default handlers.
*
* - unblock all signals,
*
* - remove all malformatted entries in the
* environment (this not containing an '=',)
*
* - set the umask to zero, to be ensure that all
* file permissions are set as specified,
*
* - change directory to '/', to ensure that the
* process does not block any mountpoint from being
* unmounted,
*
* - fork to become a background process,
*
* - temporarily become a session leader to ensure
* that the process does not have a controlling
* terminal.
*
* - fork again to become a child of the daemon
* supervisor, (subreaper could however be in the
* say, so one should not merely rely on this when
* writing a daemon supervisor,) (the first child
* shall exit after this,)
*
* - create, exclusively, a PID file to stop the daemon
* to be being run twice concurrently, and to let
* the daemon supervicer know the process ID of the
* daemon,
*
* - redirect stdin and stdout to /dev/null,
* as well as stderr if it is currently directed
* to a terminal, and
*
* - exit in the original process to let the daemon
* supervisor know that the daemon has been
* initialised.
*
* Before calling this function, you should remove any
* environment variable that could negatively impact
* the runtime of the process.
*
* After calling this function, you should remove
* unnecessary privileges.
*
* Do not try do continue the process in failure unless
* you make sure to only do this in the original process.
* But not that things will not necessarily be as when
* you make the function call. The process can have become
* partially deamonised.
*
* If $XDG_RUNTIME_DIR is set and is not empty, its value
* should be used instead of /run for the runtime data-files
* directory, in which the PID file is stored.
*
* This is a slibc extension.
*
* @etymology (Daemonise) the process!
*
* @param name The name of the daemon. Use a hardcoded value,
* not the process name. Must not be `NULL`.
* @param flags Flags to modify the behaviour of the function.
* A bitwise OR combination of the constants:
* - `DAEMONISE_NO_CLOSE`
* - `DAEMONISE_NO_SIG_DFL`
* - `DAEMONISE_KEEP_SIGMASK`
* - `DAEMONISE_KEEP_ENVIRON`
* - `DAEMONISE_KEEP_UMASK`
* - `DAEMONISE_NO_PID_FILE`
* - `DAEMONISE_KEEP_STDERR`
* - `DAEMONISE_CLOSE_STDERR`
* - `DAEMONISE_KEEP_STDIN`
* - `DAEMONISE_KEEP_STDOUT`
* @return Zero on success, -1 on error.
*
* @throws EEXIST The PID file already exists on the system.
* Unless your daemon supervisor removs old
* PID files, this could mean that the daemon
* has exited without removing the PID file.
* @throws Any error specified for signal(3).
* @throws Any error specified for sigemptyset(3).
* @throws Any error specified for sigprocmask(3).
* @throws Any error specified for chdir(3).
* @throws Any error specified for pipe(3).
* @throws Any error specified for dup2(3).
* @throws Any error specified for fork(3).
* @throws Any error specified for setsid(3).
* @throws Any error specified for open(3).
*
* @since Always.
*/
int daemonise(const char*, int)
__GCC_ONLY(__attribute__((__nonnull__, __warn_unused_result__)));
/**
* Remove the PID file created by `daemonise`. This shall
* always be called before exiting after calling `daemonise`,
* even if it failed.
*
* This is a slibc extension.
*
* @etymology (Un)link PID file created by `(daemonise)`!
*
* @return Zero on success, -1 on error.
*
* @throws Any error specified for unlink(3).
*
* @since Always.
*/
int undaemonise(void);
#endif
/**
* Get password input from the terminal.
*
* The exact behaviour of this function depends on the implementations.
* However you can assume that, the controlling terminal (/dev/tty) is
* opened and used for input and output, and that echoing is disabled.
* You cannot assume that arbitrary lengths are supported. However, in
* this implementation, line editing is enabled and arbitrary lengths
* are supported. If the length of the input (excluding termination) is
* less than 8192 a statically allocated string is returned, otherwise
* a dynamically allocated string is returned.
*
* @etymology (Get) (pass)word from terminal!
*
* @param prompt Text to print at the beginning of the line.
* Used to tell the user what is expected of her.
* Must not be `NULL`.
* @return The entered line. You should override it with zeroes as
* soon as possible to avoid leaving cleartest passphrases
* visible in memory, or potentially stored to unencrypted
* swap. The returned string is statically allocated, do
* not deallocate it, unless you know that you are using
* slibc and the length of the string is at least 8192.
* `NULL` on error. If a statically allocated string is
* returned, it will be overwritten at the next call.
*
* @throws Any error specified for open(3).
* @throws Any error specified for malloc(3).
* @throws Any error specified for read(3).
* @throws Any error specified for tcgetattr(3).
* @throws Any error specified for tcsetattr(3).
* @throws Any error specified for tcdrain(3).
*
* @since Always.
*/
char* getpass(const char*)
__GCC_ONLY(__attribute__((__nonnull__, __warn_unused_result__)))
__deprecated("'getpass' has been deprecated without any "
"replacement. You could use libpassphrase instead. :)");
#endif
/*
TODO readn(plan9), writen, preadn, pwriten
readn: read that can only return with a short read on error
writen: write that can only return with a short write on error
preadn: pread that can only return with a short read on error
pwriten: pwrite that can only return with a short write on error
*/
