tcgetpgrp(3C)                                       tcgetpgrp(3C)



NAME
     tcgetpgrp, tcsetpgrp - Get or set foreground process group
     ID.

SYNOPSIS
     #include <sys/types.h>

     pidt tcgetpgrp (fildes)
     int fildes;

     int tcsetpgrp (fildes, pgrpid)
     int fildes;
     pidt pgrpid;

DESCRIPTION
     The tcgetpgrp() and tcsetpgrp() functions are defined in the
     POSIX 1003.1 standard and used in the OCS and BCS standards.
     CX/UX applications which are not POSIX/OCS/BCS compliant can
     use these functions.

     tcgetpgrp returns the value of the process group ID of the
     foreground process group associated with the terminal device
     identified by fildes. A background process may call this
     function, but the attributes may be changed by a subsequent
     foreground process call to tcsetpgrp.

     Tcsetpgrp sets the foreground process group ID associated
     with the terminal device identified by fildes. Certain res-
     trictions apply to the use of this function:

     1.   Fildes must be the controlling terminal of the calling
          process.
     2.   This controlling terminal must be currently associated
          with the session of the calling process.
     3.   The value of pgrp_id must match a process group ID of a
          process in the same session as the calling process.

     Background processes may not call tcsetpgrp.  Attempts to do
     so will result in a SIGTTOU signal being sent to the calling
     process and all members of its process group.  The SIGTTOU
     signal stops the calling process and all members of its pro-
     cess group unless the calling process is blocking or ignor-
     ing this signal.

SEE ALSO
     getpgrp(2), setpgrp(2), setpgid(2), setsid(2), termios(7)

DIAGNOSTICS
     Upon successful completion, the value of the obtained pro-
     cess group ID is returned by tcgetpgrp and a value of zero
     is returned by tcsetpgrp.  If not, a value of -1 is returned
     and errno is set.



Page 1                        CX/UX Programmer's Reference Manual

tcgetpgrp(3C)                                       tcgetpgrp(3C)



     Errno is set to one of the following values for tcgetpgrp:

     [EBADF]        Fildes is not a valid open file descriptor.

     [ENOTTY]       Fildes is not associated with a terminal dev-
                    ice or either the calling process or its ses-
                    sion does not have a controlling terminal or
                    the terminal device is not a controlling ter-
                    minal.

     Errno is set to one of the following values for tcsetpgrp:

     [EBADF]        Fildes is not a valid open file descriptor.

     [EINVAL]       The value of pgrp_id is not a valid ID value
                    supported by CX/UX.

     [ENOTTY]       The calling process does not have a control-
                    ling terminal, or fildes is not the control-
                    ling terminal of this process, or the con-
                    trolling terminal is no longer associated
                    with the session of the calling process.

     [EPERM]        The value of pgrp_id is valid, but does not
                    match the process group ID of a process in
                    the same session as the calling process.





























Page 2                        CX/UX Programmer's Reference Manual