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TCGETPGRP(3)		   Linux Programmer's Manual		  TCGETPGRP(3)



NAME
       tcgetpgrp, tcsetpgrp - get and set terminal foreground process group

SYNOPSIS
       #include <unistd.h>

       pid_t tcgetpgrp(int fd);

       int tcsetpgrp(int fd, pid_t pgrp);

DESCRIPTION
       The function tcgetpgrp() returns the process group ID of the foreground
       process group on the terminal associated to fd, which must be the  con-
       trolling terminal of the calling process.

       The  function tcsetpgrp() makes the process group with process group ID
       pgrp the foreground process group on the	 terminal  associated  to  fd,
       which  must  be	the  controlling  terminal of the calling process, and
       still be associated  with  its  session.	  Moreover,  pgrp  must	 be  a
       (nonempty)  process  group belonging to the same session as the calling
       process.

       If tcsetpgrp() is called by a member of a background process  group  in
       its  session, and the calling process is not blocking or ignoring SIGT-
       TOU, a SIGTTOU signal is sent to all members of this background process
       group.

RETURN VALUE
       When  fd refers to the controlling terminal of the calling process, the
       function tcgetpgrp() will return the foreground	process	 group	ID  of
       that terminal if there is one, and some value larger than 1 that is not
       presently a process group ID otherwise.	When fd does not refer to  the
       controlling  terminal of the calling process, -1 is returned, and errno
       is set appropriately.

       When successful, tcsetpgrp() returns 0.	Otherwise, it returns -1,  and
       errno is set appropriately.

ERRORS
       EBADF  fd is not a valid file descriptor.

       EINVAL pgrp has an unsupported value.

       ENOTTY The  calling process does not have a controlling terminal, or it
	      has one but it is not described by fd, or, for tcsetpgrp(), this
	      controlling terminal is no longer associated with the session of
	      the calling process.

       EPERM  pgrp has a supported value, but is not the process group ID of a
	      process in the same session as the calling process.

ATTRIBUTES
       For   an	  explanation	of   the  terms	 used  in  this	 section,  see
       attributes(7).

       +-------------------------+---------------+---------+
       |Interface		 | Attribute	 | Value   |
       +-------------------------+---------------+---------+
       |tcgetpgrp(), tcsetpgrp() | Thread safety | MT-Safe |
       +-------------------------+---------------+---------+
CONFORMING TO
       POSIX.1-2001, POSIX.1-2008.

NOTES
       These functions are implemented via the TIOCGPGRP and TIOCSPGRP ioctls.

   History
       The ioctls appeared in 4.2BSD.  The functions are POSIX inventions.

SEE ALSO
       setpgid(2), setsid(2), credentials(7)

COLOPHON
       This page is part of release 4.10 of the Linux  man-pages  project.   A
       description  of	the project, information about reporting bugs, and the
       latest	 version    of	  this	  page,	   can	   be	  found	    at
       https://www.kernel.org/doc/man-pages/.



GNU				  2015-08-08			  TCGETPGRP(3)