php man page for posix_getpgrp

POSIX_GETPGRP(3)							 1							  POSIX_GETPGRP(3)

posix_getpgrp - Return the current process group identifier

SYNOPSIS
       int posix_getpgrp (void	)

DESCRIPTION
	Return the process group identifier of the current process.

RETURN VALUES
	Returns the identifier, as an integer.

SEE ALSO
       POSIX.1 and the getpgrp(2) manual page on the POSIX system for more information on process groups..

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