CATCHOUT(3PVM)							  PVM Version 3.4						    CATCHOUT(3PVM)

NAME

       pvm_catchout - Catch output from child tasks.

SYNOPSIS

       C    #include <stdio.h>

	    int info = pvm_catchout( FILE *ff )

       Fortran	 call pvmfcatchout( onoff, info )

PARAMETERS

       ff      File descriptor on which to write collected output.

       onoff   Integer parameter.  Turns output collection on or off.

       info    Integer status code returned by the routine.  Values less than zero indicate an error.

DESCRIPTION

       The routine pvm_catchout causes the calling task (the parent) to catch output from any tasks spawned after the call to pvm_catchout.  Char-
       acters printed on stdout or stderr in children tasks are collected by the pvmds and sent in control messages to the parent task, which tags
       each  line  and	appends  it  to the specified file.  Output from grandchildren (spawned by children) tasks is also collected, provided the
       children don't reset their PvmOutputTid.

       If option PvmShowTids (see pvm_setopt) is true (nonzero), output is printed as shown below, tagged with the task id where the output origi-
       nated:
	    [txxxxx] BEGIN
	    [txxxxx] (text from child task)
	    [txxxxx] END

       The output from each task includes one BEGIN line and one END line, with whatever the task prints in between.  If PvmShowTids is false, raw
       output is printed with no additional information.

       In C, the output file descriptor may be specified.  Giving a null pointer turns output collection off for any  subsequently  spawned  child
       tasks.	(Any existing output collection will still proceed at the child tasks, until they exit or change theirPvmOutputTid or related set-
       tings - see man page for pvm_setopt().)	In Fortran, output collection can only be turned on or off (again only	for  subsequently  spawned
       child tasks), and is always logged to the stdout of the parent task.

       If  pvm_exit  is  called  while output collection is in effect, it will block in order to print all the output, until all tasks sending the
       given task output have exited.  To avoid this, output collection can be turned off by calling pvm_catchout(0) before calling pvm_exit.

       pvm_catchout() always returns 0.

EXAMPLES

       C:
	    #include <stdio.h>

	    pvm_catchout(stdout);

       Fortran:
	    CALL PVMFCATCHOUT( 1, INFO )

SEE ALSO

       pvm_exit(3PVM), pvm_setopt(3PVM), pvm_spawn(3PVM)

								   13 July, 1994						    CATCHOUT(3PVM)