tcgetpgrp(3C)tcgetpgrp(3C)NAMEtcgetpgrp() - get foreground process group id
SYNOPSISDESCRIPTION
returns the value of the process group ID of the foreground process
group associated with the terminal referenced by fildes. is allowed
from a process that is a member of a background process group (see
termio(7)); however, the information can be subsequently changed by a
process that is a member of a foreground process group.
RETURN VALUE
Upon successful completion, returns the value of the process group ID
of the foreground process group associated with the terminal referenced
by fildes. Otherwise, returns a value of −1 and sets to indicate the
error.
ERRORS
fails if any of the following conditions are encountered:
The file associated with
fildes is the controlling terminal of the calling
process, however, there is no foreground process
group defined for the controlling terminal.
fildes is not a valid file descriptor.
The file associated with
fildes is not the controlling terminal or the
calling process does not have a controlling ter‐
minal.
WARNINGS
The error which is returned if the controlling terminal has no fore‐
ground process group, might not be returned in future releases, depend‐
ing on the course taken by the POSIX standard. Portable applications
therefore should not rely on this error condition.
SEE ALSOsetpgid(2), setsid(2), tcsetpgrp(3C), thread_safety(5), termio(7).
STANDARDS CONFORMANCEtcgetpgrp(3C)