summaryrefslogtreecommitdiffstats
path: root/man3/posix_spawn.3
diff options
context:
space:
mode:
Diffstat (limited to 'man3/posix_spawn.3')
-rw-r--r--man3/posix_spawn.3823
1 files changed, 0 insertions, 823 deletions
diff --git a/man3/posix_spawn.3 b/man3/posix_spawn.3
deleted file mode 100644
index 8fa746f..0000000
--- a/man3/posix_spawn.3
+++ /dev/null
@@ -1,823 +0,0 @@
-.\" Copyright (c) 2009 Bill O. Gallmeister (bgallmeister@gmail.com)
-.\" and Copyright 2010 Michael Kerrisk <mtk.manpages@gmail.com>
-.\"
-.\" SPDX-License-Identifier: Linux-man-pages-copyleft
-.\"
-.\" References consulted:
-.\" Linux glibc source code
-.\" POSIX 1003.1-2004 documentation
-.\" (http://www.opengroup.org/onlinepubs/009695399)
-.\"
-.TH posix_spawn 3 2023-10-31 "Linux man-pages 6.7"
-.SH NAME
-posix_spawn, posix_spawnp \- spawn a process
-.SH LIBRARY
-Standard C library
-.RI ( libc ", " \-lc )
-.SH SYNOPSIS
-.nf
-.B #include <spawn.h>
-.P
-.BI "int posix_spawn(pid_t *restrict " pid ", const char *restrict " path ,
-.BI " const posix_spawn_file_actions_t *restrict " file_actions ,
-.BI " const posix_spawnattr_t *restrict " attrp ,
-.BI " char *const " argv [restrict],
-.BI " char *const " envp [restrict]);
-.BI "int posix_spawnp(pid_t *restrict " pid ", const char *restrict " file ,
-.BI " const posix_spawn_file_actions_t *restrict " file_actions ,
-.BI " const posix_spawnattr_t *restrict " attrp ,
-.BI " char *const " argv [restrict],
-.BI " char *const " envp [restrict]);
-.fi
-.SH DESCRIPTION
-The
-.BR posix_spawn ()
-and
-.BR posix_spawnp ()
-functions are used to create a new child process that executes
-a specified file.
-These functions were specified by POSIX to provide a standardized method
-of creating new processes on machines that lack the capability
-to support the
-.BR fork (2)
-system call.
-These machines are generally small, embedded systems lacking MMU support.
-.P
-The
-.BR posix_spawn ()
-and
-.BR posix_spawnp ()
-functions provide the functionality of a combined
-.BR fork (2)
-and
-.BR exec (3),
-with some optional housekeeping steps in the child process before the
-.BR exec (3).
-These functions are not meant to replace the
-.BR fork (2)
-and
-.BR execve (2)
-system calls.
-In fact, they provide only a subset of the functionality
-that can be achieved by using the system calls.
-.P
-The only difference between
-.BR posix_spawn ()
-and
-.BR posix_spawnp ()
-is the manner in which they specify the file to be executed by
-the child process.
-With
-.BR posix_spawn (),
-the executable file is specified as a pathname
-(which can be absolute or relative).
-With
-.BR posix_spawnp (),
-the executable file is specified as a simple filename;
-the system searches for this file in the list of directories specified by
-.B PATH
-(in the same way as for
-.BR execvp (3)).
-For the remainder of this page, the discussion is phrased in terms of
-.BR posix_spawn (),
-with the understanding that
-.BR posix_spawnp ()
-differs only on the point just described.
-.P
-The remaining arguments to these two functions are as follows:
-.TP
-.I pid
-points to a buffer that is used to return the process ID
-of the new child process.
-.TP
-.I file_actions
-points to a
-.I "spawn file actions object"
-that specifies file-related actions to be performed in the child
-between the
-.BR fork (2)
-and
-.BR exec (3)
-steps.
-This object is initialized and populated before the
-.BR posix_spawn ()
-call using
-.BR posix_spawn_file_actions_init (3)
-and the
-.BR posix_spawn_file_actions_* ()
-functions.
-.TP
-.I attrp
-points to an
-.I attributes objects
-that specifies various attributes of the created child process.
-This object is initialized and populated before the
-.BR posix_spawn ()
-call using
-.BR posix_spawnattr_init (3)
-and the
-.BR posix_spawnattr_* ()
-functions.
-.TP
-.I argv
-.TQ
-.I envp
-specify the argument list and environment for the program
-that is executed in the child process, as for
-.BR execve (2).
-.P
-Below, the functions are described in terms of a three-step process: the
-.BR fork ()
-step, the
-.RB pre- exec ()
-step (executed in the child),
-and the
-.BR exec ()
-step (executed in the child).
-.SS fork() step
-Since glibc 2.24, the
-.BR posix_spawn ()
-function commences by calling
-.BR clone (2)
-with
-.B CLONE_VM
-and
-.B CLONE_VFORK
-flags.
-Older implementations use
-.BR fork (2),
-or possibly
-.BR vfork (2)
-(see below).
-.P
-The PID of the new child process is placed in
-.IR *pid .
-The
-.BR posix_spawn ()
-function then returns control to the parent process.
-.P
-Subsequently, the parent can use one of the system calls described in
-.BR wait (2)
-to check the status of the child process.
-If the child fails in any of the housekeeping steps described below,
-or fails to execute the desired file,
-it exits with a status of 127.
-.P
-Before glibc 2.24, the child process is created using
-.BR vfork (2)
-instead of
-.BR fork (2)
-when either of the following is true:
-.IP \[bu] 3
-the
-.I spawn-flags
-element of the attributes object pointed to by
-.I attrp
-contains the GNU-specific flag
-.BR POSIX_SPAWN_USEVFORK ;
-or
-.IP \[bu]
-.I file_actions
-is NULL and the
-.I spawn-flags
-element of the attributes object pointed to by
-.I attrp
-does \fInot\fP contain
-.BR POSIX_SPAWN_SETSIGMASK ,
-.BR POSIX_SPAWN_SETSIGDEF ,
-.BR POSIX_SPAWN_SETSCHEDPARAM ,
-.BR POSIX_SPAWN_SETSCHEDULER ,
-.BR POSIX_SPAWN_SETPGROUP ,
-or
-.BR POSIX_SPAWN_RESETIDS .
-.P
-In other words,
-.BR vfork (2)
-is used if the caller requests it,
-or if there is no cleanup expected in the child before it
-.BR exec (3)s
-the requested file.
-.SS pre-exec() step: housekeeping
-In between the
-.B fork()
-and the
-.B exec()
-steps, a child process may need to perform a set of housekeeping actions.
-The
-.BR posix_spawn ()
-and
-.BR posix_spawnp ()
-functions support a small, well-defined set of system tasks that the child
-process can accomplish before it executes the executable file.
-These operations are controlled by the attributes object pointed to by
-.I attrp
-and the file actions object pointed to by
-.IR file_actions .
-In the child, processing is done in the following sequence:
-.IP (1) 5
-Process attribute actions: signal mask, signal default handlers,
-scheduling algorithm and parameters,
-process group, and effective user and group IDs
-are changed as specified by the attributes object pointed to by
-.IR attrp .
-.IP (2)
-File actions, as specified in the
-.I file_actions
-argument,
-are performed in the order that they were specified using calls to the
-.BR posix_spawn_file_actions_add* ()
-functions.
-.IP (3)
-File descriptors with the
-.B FD_CLOEXEC
-flag set are closed.
-.P
-All process attributes in the child,
-other than those affected by attributes specified in the
-object pointed to by
-.I attrp
-and the file actions in the object pointed to by
-.IR file_actions ,
-will be affected as though the child was created with
-.BR fork (2)
-and it executed the program with
-.BR execve (2).
-.P
-The process attributes actions are defined by the attributes object
-pointed to by
-.IR attrp .
-The
-.I spawn-flags
-attribute (set using
-.BR posix_spawnattr_setflags (3))
-controls the general actions that occur,
-and other attributes in the object specify values
-to be used during those actions.
-.P
-The effects of the flags that may be specified in
-.I spawn-flags
-are as follows:
-.TP
-.B POSIX_SPAWN_SETSIGMASK
-Set the signal mask to the signal set specified in the
-.I spawn-sigmask
-attribute
-.\" FIXME .
-.\" (see
-.\" .BR posix_spawnattr_setsigmask (3))
-of the object pointed to by
-.IR attrp .
-If the
-.B POSIX_SPAWN_SETSIGMASK
-flag is not set, then the child inherits the parent's signal mask.
-.TP
-.B POSIX_SPAWN_SETSIGDEF
-Reset the disposition of all signals in the set specified in the
-.I spawn-sigdefault
-attribute
-.\" FIXME .
-.\" (see
-.\" .BR posix_spawnattr_setsigdefault (3))
-of the object pointed to by
-.I attrp
-to the default.
-For the treatment of the dispositions of signals not specified in the
-.I spawn-sigdefault
-attribute, or the treatment when
-.B POSIX_SPAWN_SETSIGDEF
-is not specified, see
-.BR execve (2).
-.TP
-.B POSIX_SPAWN_SETSCHEDPARAM
-.\" (POSIX_PRIORITY_SCHEDULING only)
-If this flag is set, and the
-.B POSIX_SPAWN_SETSCHEDULER
-flag is not set, then set the scheduling parameters
-to the parameters specified in the
-.I spawn-schedparam
-attribute
-.\" FIXME .
-.\" (see
-.\" .BR posix_spawnattr_setschedparam (3))
-of the object pointed to by
-.IR attrp .
-.TP
-.B POSIX_SPAWN_SETSCHEDULER
-Set the scheduling policy algorithm and parameters of the child,
-as follows:
-.RS
-.IP \[bu] 3
-The scheduling policy is set to the value specified in the
-.I spawn-schedpolicy
-attribute
-.\" FIXME .
-.\" (see
-.\" .BR posix_spawnattr_setpolicy (3))
-of the object pointed to by
-.IR attrp .
-.IP \[bu]
-The scheduling parameters are set to the value specified in the
-.I spawn-schedparam
-attribute
-.\" FIXME .
-.\" (see
-.\" .BR posix_spawnattr_setschedparam (3))
-of the object pointed to by
-.I attrp
-(but see BUGS).
-.P
-If the
-.B POSIX_SPAWN_SETSCHEDPARAM
-and
-.B POSIX_SPAWN_SETSCHEDPOLICY
-flags are not specified,
-the child inherits the corresponding scheduling attributes from the parent.
-.RE
-.TP
-.B POSIX_SPAWN_RESETIDS
-If this flag is set,
-reset the effective UID and GID to the
-real UID and GID of the parent process.
-If this flag is not set,
-then the child retains the effective UID and GID of the parent.
-In either case, if the set-user-ID and set-group-ID permission
-bits are enabled on the executable file, their effect will override
-the setting of the effective UID and GID (se
-.BR execve (2)).
-.TP
-.B POSIX_SPAWN_SETPGROUP
-Set the process group to the value specified in the
-.I spawn-pgroup
-attribute
-.\" FIXME .
-.\" (see
-.\" .BR posix_spawnattr_setpgroup (3))
-of the object pointed to by
-.IR attrp .
-If the
-.I spawn-pgroup
-attribute has the value 0,
-the child's process group ID is made the same as its process ID.
-If the
-.B POSIX_SPAWN_SETPGROUP
-flag is not set, the child inherits the parent's process group ID.
-.TP
-.B POSIX_SPAWN_USEVFORK
-Since glibc 2.24, this flag has no effect.
-On older implementations, setting this flag forces the
-.B fork()
-step to use
-.BR vfork (2)
-instead of
-.BR fork (2).
-The
-.B _GNU_SOURCE
-feature test macro must be defined to obtain the definition of this constant.
-.TP
-.BR POSIX_SPAWN_SETSID " (since glibc 2.26)"
-If this flag is set,
-the child process shall create a new session and become the session leader.
-The child process shall also become the process group leader of the new process
-group in the session (see
-.BR setsid (2)).
-The
-.B _GNU_SOURCE
-feature test macro must be defined to obtain the definition of this constant.
-.\" This flag has been accepted in POSIX, see:
-.\" http://austingroupbugs.net/view.php?id=1044
-.\" and has been implemented since glibc 2.26
-.\" commit daeb1fa2e1b33323e719015f5f546988bd4cc73b
-.P
-If
-.I attrp
-is NULL, then the default behaviors described above for each flag apply.
-.\" mtk: I think we probably don't want to say the following, since it
-.\" could lead people to do the wrong thing
-.\" The POSIX standard tells you to call
-.\" this function to de-initialize the attributes object pointed to by
-.\" .I attrp
-.\" when you are done with it;
-.\" however, on Linux systems this operation is a no-op.
-.P
-The
-.I file_actions
-argument specifies a sequence of file operations
-that are performed in the child process after
-the general processing described above, and before it performs the
-.BR exec (3).
-If
-.I file_actions
-is NULL, then no special action is taken, and standard
-.BR exec (3)
-semantics apply\[em]file descriptors open before the exec
-remain open in the new process,
-except those for which the
-.B FD_CLOEXEC
-flag has been set.
-File locks remain in place.
-.P
-If
-.I file_actions
-is not NULL, then it contains an ordered set of requests to
-.BR open (2),
-.BR close (2),
-and
-.BR dup2 (2)
-files.
-These requests are added to the
-.I file_actions
-by
-.BR posix_spawn_file_actions_addopen (3),
-.BR posix_spawn_file_actions_addclose (3),
-and
-.BR posix_spawn_file_actions_adddup2 (3).
-The requested operations are performed in the order they were added to
-.IR file_actions .
-.\" FIXME . I think the following is best placed in the
-.\" posix_spawn_file_actions_adddup2(3) page, and a similar statement is
-.\" also needed in posix_spawn_file_actions_addclose(3)
-.\" Note that you can specify file descriptors in
-.\" .I posix_spawn_file_actions_adddup2 (3)
-.\" which would not be usable if you called
-.\" .BR dup2 (2)
-.\" at that time--i.e., file descriptors that are opened or
-.\" closed by the earlier operations
-.\" added to
-.\" .I file_actions .
-.P
-If any of the housekeeping actions fails
-(due to bogus values being passed or other reasons why signal handling,
-process scheduling, process group ID functions,
-and file descriptor operations might fail),
-the child process exits with exit value 127.
-.SS exec() step
-Once the child has successfully forked and performed
-all requested pre-exec steps,
-the child runs the requested executable.
-.P
-The child process takes its environment from the
-.I envp
-argument, which is interpreted as if it had been passed to
-.BR execve (2).
-The arguments to the created process come from the
-.I argv
-argument, which is processed as for
-.BR execve (2).
-.SH RETURN VALUE
-Upon successful completion,
-.BR posix_spawn ()
-and
-.BR posix_spawnp ()
-place the PID of the child process in
-.IR pid ,
-and return 0.
-If there is an error during the
-.B fork()
-step,
-then no child is created,
-the contents of
-.I *pid
-are unspecified,
-and these functions return an error number as described below.
-.P
-Even when these functions return a success status,
-the child process may still fail for a plethora of reasons related to its
-pre-\fBexec\fR() initialization.
-In addition, the
-.BR exec (3)
-may fail.
-In all of these cases, the child process will exit with the exit value of 127.
-.SH ERRORS
-The
-.BR posix_spawn ()
-and
-.BR posix_spawnp ()
-functions fail only in the case where the underlying
-.BR fork (2),
-.BR vfork (2),
-or
-.BR clone (2)
-call fails; in these cases, these functions return an error number,
-which will be one of the errors described for
-.BR fork (2),
-.BR vfork (2),
-or
-.BR clone (2).
-.P
-In addition, these functions fail if:
-.TP
-.B ENOSYS
-Function not supported on this system.
-.SH STANDARDS
-POSIX.1-2008.
-.SH HISTORY
-glibc 2.2.
-POSIX.1-2001.
-.\" FIXME . This piece belongs in spawnattr_setflags(3)
-.\" The
-.\" .B POSIX_SPAWN_USEVFORK
-.\" flag is a GNU extension; the
-.\" .B _GNU_SOURCE
-.\" feature test macro must be defined (before including any header files)
-.\" to obtain the definition of this constant.
-.SH NOTES
-The housekeeping activities in the child are controlled by
-the objects pointed to by
-.I attrp
-(for non-file actions) and
-.I file_actions
-In POSIX parlance, the
-.I posix_spawnattr_t
-and
-.I posix_spawn_file_actions_t
-data types are referred to as objects,
-and their elements are not specified by name.
-Portable programs should initialize these objects using
-only the POSIX-specified functions.
-(In other words,
-although these objects may be implemented as structures containing fields,
-portable programs must avoid dependence on such implementation details.)
-.P
-According to POSIX, it is unspecified whether fork handlers established with
-.BR pthread_atfork (3)
-are called when
-.BR posix_spawn ()
-is invoked.
-Since glibc 2.24, the fork handlers are not executed in any case.
-.\" Tested on glibc 2.12
-On older implementations,
-fork handlers are called only if the child is created using
-.BR fork (2).
-.P
-There is no "posix_fspawn" function (i.e., a function that is to
-.BR posix_spawn ()
-as
-.BR fexecve (3)
-is to
-.BR execve (2)).
-However, this functionality can be obtained by specifying the
-.I path
-argument as one of the files in the caller's
-.I /proc/self/fd
-directory.
-.SH BUGS
-POSIX.1 says that when
-.B POSIX_SPAWN_SETSCHEDULER
-is specified in
-.IR spawn-flags ,
-then the
-.B POSIX_SPAWN_SETSCHEDPARAM
-(if present) is ignored.
-However, before glibc 2.14, calls to
-.BR posix_spawn ()
-failed with an error if
-.\" http://sourceware.org/bugzilla/show_bug.cgi?id=12052
-.B POSIX_SPAWN_SETSCHEDULER
-was specified without also specifying
-.BR POSIX_SPAWN_SETSCHEDPARAM .
-.SH EXAMPLES
-The program below demonstrates the use of various functions in the
-POSIX spawn API.
-The program accepts command-line attributes that can be used
-to create file actions and attributes objects.
-The remaining command-line arguments are used as the executable name
-and command-line arguments of the program that is executed in the child.
-.P
-In the first run, the
-.BR date (1)
-command is executed in the child, and the
-.BR posix_spawn ()
-call employs no file actions or attributes objects.
-.P
-.in +4n
-.EX
-$ \fB./a.out date\fP
-PID of child: 7634
-Tue Feb 1 19:47:50 CEST 2011
-Child status: exited, status=0
-.EE
-.in
-.P
-In the next run, the
-.I \-c
-command-line option is used to create a file actions object that closes
-standard output in the child.
-Consequently,
-.BR date (1)
-fails when trying to perform output and exits with a status of 1.
-.P
-.in +4n
-.EX
-$ \fB./a.out \-c date\fP
-PID of child: 7636
-date: write error: Bad file descriptor
-Child status: exited, status=1
-.EE
-.in
-.P
-In the next run, the
-.I \-s
-command-line option is used to create an attributes object that
-specifies that all (blockable) signals in the child should be blocked.
-Consequently, trying to kill child with the default signal sent by
-.BR kill (1)
-(i.e.,
-.BR SIGTERM )
-fails, because that signal is blocked.
-Therefore, to kill the child,
-.B SIGKILL
-is necessary
-.RB ( SIGKILL
-can't be blocked).
-.P
-.in +4n
-.EX
-$ \fB./a.out \-s sleep 60 &\fP
-[1] 7637
-$ PID of child: 7638
-.P
-$ \fBkill 7638\fP
-$ \fBkill \-KILL 7638\fP
-$ Child status: killed by signal 9
-[1]+ Done ./a.out \-s sleep 60
-.EE
-.in
-.P
-When we try to execute a nonexistent command in the child, the
-.BR exec (3)
-fails and the child exits with a status of 127.
-.P
-.in +4n
-.EX
-$ \fB./a.out xxxxx
-PID of child: 10190
-Child status: exited, status=127
-.EE
-.in
-.SS Program source
-\&
-.\" SRC BEGIN (posix_spawn.c)
-.EX
-#include <errno.h>
-#include <spawn.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-#include <wait.h>
-\&
-#define errExit(msg) do { perror(msg); \e
- exit(EXIT_FAILURE); } while (0)
-\&
-#define errExitEN(en, msg) \e
- do { errno = en; perror(msg); \e
- exit(EXIT_FAILURE); } while (0)
-\&
-char **environ;
-\&
-int
-main(int argc, char *argv[])
-{
- pid_t child_pid;
- int s, opt, status;
- sigset_t mask;
- posix_spawnattr_t attr;
- posix_spawnattr_t *attrp;
- posix_spawn_file_actions_t file_actions;
- posix_spawn_file_actions_t *file_actionsp;
-\&
- /* Parse command\-line options, which can be used to specify an
- attributes object and file actions object for the child. */
-\&
- attrp = NULL;
- file_actionsp = NULL;
-\&
- while ((opt = getopt(argc, argv, "sc")) != \-1) {
- switch (opt) {
- case \[aq]c\[aq]: /* \-c: close standard output in child */
-\&
- /* Create a file actions object and add a "close"
- action to it. */
-\&
- s = posix_spawn_file_actions_init(&file_actions);
- if (s != 0)
- errExitEN(s, "posix_spawn_file_actions_init");
-\&
- s = posix_spawn_file_actions_addclose(&file_actions,
- STDOUT_FILENO);
- if (s != 0)
- errExitEN(s, "posix_spawn_file_actions_addclose");
-\&
- file_actionsp = &file_actions;
- break;
-\&
- case \[aq]s\[aq]: /* \-s: block all signals in child */
-\&
- /* Create an attributes object and add a "set signal mask"
- action to it. */
-\&
- s = posix_spawnattr_init(&attr);
- if (s != 0)
- errExitEN(s, "posix_spawnattr_init");
- s = posix_spawnattr_setflags(&attr, POSIX_SPAWN_SETSIGMASK);
- if (s != 0)
- errExitEN(s, "posix_spawnattr_setflags");
-\&
- sigfillset(&mask);
- s = posix_spawnattr_setsigmask(&attr, &mask);
- if (s != 0)
- errExitEN(s, "posix_spawnattr_setsigmask");
-\&
- attrp = &attr;
- break;
- }
- }
-\&
- /* Spawn the child. The name of the program to execute and the
- command\-line arguments are taken from the command\-line arguments
- of this program. The environment of the program execed in the
- child is made the same as the parent\[aq]s environment. */
-\&
- s = posix_spawnp(&child_pid, argv[optind], file_actionsp, attrp,
- &argv[optind], environ);
- if (s != 0)
- errExitEN(s, "posix_spawn");
-\&
- /* Destroy any objects that we created earlier. */
-\&
- if (attrp != NULL) {
- s = posix_spawnattr_destroy(attrp);
- if (s != 0)
- errExitEN(s, "posix_spawnattr_destroy");
- }
-\&
- if (file_actionsp != NULL) {
- s = posix_spawn_file_actions_destroy(file_actionsp);
- if (s != 0)
- errExitEN(s, "posix_spawn_file_actions_destroy");
- }
-\&
- printf("PID of child: %jd\en", (intmax_t) child_pid);
-\&
- /* Monitor status of the child until it terminates. */
-\&
- do {
- s = waitpid(child_pid, &status, WUNTRACED | WCONTINUED);
- if (s == \-1)
- errExit("waitpid");
-\&
- printf("Child status: ");
- if (WIFEXITED(status)) {
- printf("exited, status=%d\en", WEXITSTATUS(status));
- } else if (WIFSIGNALED(status)) {
- printf("killed by signal %d\en", WTERMSIG(status));
- } else if (WIFSTOPPED(status)) {
- printf("stopped by signal %d\en", WSTOPSIG(status));
- } else if (WIFCONTINUED(status)) {
- printf("continued\en");
- }
- } while (!WIFEXITED(status) && !WIFSIGNALED(status));
-\&
- exit(EXIT_SUCCESS);
-}
-.EE
-.\" SRC END
-.SH SEE ALSO
-.nh \" Disable hyphenation
-.ad l
-.BR close (2),
-.BR dup2 (2),
-.BR execl (2),
-.BR execlp (2),
-.BR fork (2),
-.BR open (2),
-.BR sched_setparam (2),
-.BR sched_setscheduler (2),
-.BR setpgid (2),
-.BR setuid (2),
-.BR sigaction (2),
-.BR sigprocmask (2),
-.BR posix_spawn_file_actions_addclose (3),
-.BR posix_spawn_file_actions_adddup2 (3),
-.BR posix_spawn_file_actions_addopen (3),
-.BR posix_spawn_file_actions_destroy (3),
-.BR posix_spawn_file_actions_init (3),
-.BR posix_spawnattr_destroy (3),
-.BR posix_spawnattr_getflags (3),
-.BR posix_spawnattr_getpgroup (3),
-.BR posix_spawnattr_getschedparam (3),
-.BR posix_spawnattr_getschedpolicy (3),
-.BR posix_spawnattr_getsigdefault (3),
-.BR posix_spawnattr_getsigmask (3),
-.BR posix_spawnattr_init (3),
-.BR posix_spawnattr_setflags (3),
-.BR posix_spawnattr_setpgroup (3),
-.BR posix_spawnattr_setschedparam (3),
-.BR posix_spawnattr_setschedpolicy (3),
-.BR posix_spawnattr_setsigdefault (3),
-.BR posix_spawnattr_setsigmask (3),
-.BR pthread_atfork (3),
-.IR <spawn.h> ,
-Base Definitions volume of POSIX.1-2001,
-.I http://www.opengroup.org/unix/online.html