Unknown option: "-2" Unix manual page for killpg. (host=minya system=Darwin)
KILLPG(2)                   BSD System Calls Manual                  KILLPG(2)

NAME
     killpg -- send signal to a process group

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <signal.h>

     int
     killpg(pid_t pgrp, int sig);

DESCRIPTION
     The killpg() function sends the signal sig to the process group pgrp.
     See sigaction(2) for a list of signals.  If pgrp is 0, killpg() sends the
     signal to the sending process's process group.

     The sending process and members of the process group must have the same
     effective user ID, or the sender must be the super-user.  As a single
     special case the continue signal SIGCONT may be sent to any process with
     the same session ID as the caller.

RETURN VALUES
     The killpg() function returns the value 0 if successful; otherwise the
     value -1 is returned and the global variable errno is set to indicate the
     error.

ERRORS
     The killpg() function will fail and no signal will be sent if:

     [EINVAL]           The sig argument is not a valid signal number.

     [EPERM]            The sending process is not the super-user and one or
                        more of the target processes has an effective user ID
                        different from that of the sending process.

     [ESRCH]            No process can be found in the process group specified
                        by pgrp.

     [ESRCH]            The process group was given as 0 but the sending
                        process does not have a process group.

LEGACY SYNOPSIS
     #include <sys/types.h>
     #include <signal.h>

     The include file <sys/types.h> is necessary.

SEE ALSO
     getpgrp(2), kill(2), sigaction(2), compat(5)

HISTORY
     The killpg() function appeared in 4.0BSD.

BSD                            October 10, 2006                            BSD