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SETPGID(2)                  BSD System Calls Manual                 SETPGID(2)

NAME
     setpgid, setpgrp -- set process group

SYNOPSIS
     #include <unistd.h>

     int
     setpgid(pid_t pid, pid_t pgid);

     pid_t
     setpgrp(void);

DESCRIPTION
     Setpgid() sets the process group of the specified process pid to the specified pgid.  If pid is zero,
     then the call applies to the current process.

     If the invoker is not the super-user, then the affected process must have the same effective user-id as
     the invoker or be a descendant of the invoking process.

     If the calling process is not already a session leader, setpgrp() sets the process group ID of the
     calling process to that of the calling process.  Any new session that this creates will have no con-trolling controlling
     trolling terminal.

RETURN VALUES
     Setpgid() returns 0 when the operation was successful.  If the request failed, -1 is returned and the
     global variable errno indicates the reason.

ERRORS
     Setpgid() will fail and the process group will not be altered if:

     [EACCES]           The value of the pid argument matches the process ID of a child process of the call-ing calling
                        ing process, and the child process has successfully executed one of the exec func-tions. functions.
                        tions.

     [EINVAL]           The value of the pgid argument is less than 0 or is not a value supported by the
                        implementation.

     [EPERM]            The process indicated by the pid argument is a session leader.

     [EPERM]            The effective user ID of the requested process is different from that of the caller
                        and the process is not a descendant of the calling process.

     [EPERM]            The value of the pgid argument is valid, but does not match the process ID of the
                        process indicated by the pid argument and there is no process with a process group
                        ID that matches the value of the pgid argument in the same session as the calling
                        process.

     [ESRCH]            The value of the pid argument does not match the process ID of the calling process
                        or of a child process of the calling process.

LEGACY SYNOPSIS
     #include <unistd.h>

     int
     setpgrp(pid_t pid, pid_t pgid);

     The legacy setpgrp() function is a clone of the setpgid() function, retained for calling convention
     compatibility with historical versions of BSD.

COMPATIBILITY
     Use of the legacy version of the setpgrp() call will cause compiler diagnostics.  Use setpgid()
     instead.

     Use of private (and conflicting) prototypes for setpgrp() will cause compiler diagnostics.  Delete the
     private prototypes and include <unistd.h>.

SEE ALSO
     getpgrp(2), compat(5)

STANDARDS
     The setpgid() function conforms to IEEE Std 1003.1-1988 (``POSIX.1'').

4th Berkeley Distribution        June 4, 1993        4th Berkeley Distribution