TCGETPGRP(3POSIX)

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
tcgetpgrp — get the foreground process group ID

SYNOPSIS

#include <unistd.h>

pid_t tcgetpgrp(int fildes);

DESCRIPTION
The tcgetpgrp() function shall return the value of the process group ID of the foreground process group associated with the terminal.

If there is no foreground process group, tcgetpgrp() shall return a value greater than 1 that does not match the process group ID of any existing process group.

The tcgetpgrp() function is allowed from a process that is a member of a background process group; however, the information may be subsequently changed by a process that is a member of a foreground process group.

RETURN VALUE
Upon successful completion, tcgetpgrp() shall return the value of the process group ID of the foreground process associated with the terminal. Otherwise, -1 shall be returned and errno set to indicate the error.

ERRORS
The tcgetpgrp() function shall fail if:

EBADF
    The fildes argument is not a valid file descriptor.

ENOTTY
    The calling process does not have a controlling terminal, or the file is not the controlling terminal.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
None.

RATIONALE
None.

FUTURE DIRECTIONS
None.

SEE ALSO
setsid(), setpgid(), tcsetpgrp()

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 .