tcsetpgrp

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 fore-
       ground process group on the terminal associated to fd, which  must  be
       the controlling 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	 pro-
       cess 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.

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

       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 ses-
	      sion of the calling process.

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

HISTORY
       These ioctls appeared in 4.2 BSD. The functions are POSIX  inventions.

CONFORMS TO
       POSIX.1

SEE ALSO
       setpgid(2), setsid(2)



POSIX				  2003-01-28			 TCGETPGRP(3)