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PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface
may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface
may not be implemented on Linux.
NAME
tcsetpgrp — set the foreground process group ID
SYNOPSIS
#include <unistd.h>
int tcsetpgrp(int fildes, pid_t pgid_id);
DESCRIPTION
If the process has a controlling terminal, tcsetpgrp() shall set the foreground process group ID
associated with the terminal to pgid_id. The application shall ensure that the file associated with
fildes is the controlling terminal of the calling process and the controlling terminal is currently
associated with the session of the calling process. The application shall ensure that the value of
pgid_id matches a process group ID of a process in the same session as the calling process.
Attempts to use tcsetpgrp() from a process which is a member of a background process group on a fildes
associated with its controlling terminal shall cause the process group to be sent a SIGTTOU signal. If
the calling thread is blocking SIGTTOU signals or the process is ignoring SIGTTOU signals, the process
shall be allowed to perform the operation, and no signal is sent.
RETURN VALUE
Upon successful completion, 0 shall be returned. Otherwise, -1 shall be returned and errno set to
indicate the error.
ERRORS
The tcsetpgrp() function shall fail if:
EBADF The fildes argument is not a valid file descriptor.
EINVAL This implementation does not support the value in the pgid_id argument.
EIO The process group of the writing process is orphaned, the calling thread is not blocking SIGTTOU,
and the process is not ignoring SIGTTOU.
ENOTTY The calling process does not have a controlling terminal, or the file is not the controlling
terminal, or the controlling terminal is no longer associated with the session of the calling
process.
EPERM The value of pgid_id is a value supported by the implementation, but does not match the process
group ID of a process in the same session as the calling process.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
tcgetpgrp()
The Base Definitions volume of POSIX.1‐2017, <sys_types.h>, <unistd.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard
for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original
IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document.
The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .
Any typographical or formatting errors that appear in this page are most likely to have been introduced
during the conversion of the source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2017 TCSETPGRP(3POSIX)