baby(1) [debian man page]

BABY(1) 						      General Commands Manual							   BABY(1)

NAME

       baby -- create new process from two parents

SYNOPSIS

       baby -sex [m|f] [-name name]

DESCRIPTION

       baby  is  initiated when one parent process polls another server process through a socket connection in the BSD version or through pipes in
       the System V implementation.  baby runs at low priority for approximately forty weeks and then terminates with a heavy system  load.   Most
       systems require constant monitoring when baby reaches its final stages of execution.

       Older  implementations  of  baby  did not require both initiating processes to be present at the time of completion.  In those versions the
       initiating process which was not present was awakened and notified of the results upon completion.  It has since been determined  that  the
       presence of both parent processes result in a generally lower system load at completion, and thus current versions of baby expect both par-
       ent processes to be active during the final stages.

       Successful completion of baby results in the creation and naming of a new process.  Parent processes then broadcast messages to	all  other
       processes, local and remote, informing them of their new status.

OPTIONS

       -sex   define the gender of the created process

       -name  assign the name name to the new process

EXAMPLES

	      baby -sex f -name Jacqueline

       completed  successfully	on  July  9, 1992 at 9:11pm.  Jacqueline's vital statistics: 8 pounds 3 oz, 20 inches, long dark hair.	The parent
       process, Kim Dunbar, is reportedly doing fine.

SEE ALSO

       cigar(6), dump(5), cry(3).

BUGS

       Despite its complexity, baby only knows one signal, SIGCHLD, (or SIGCLD in the System V implementation), which it uses to contact the  par-
       ent processes.  One or both parent processes must then inspect the baby process to determine the cause of the signal.

       The  sleep(1)  command may not work as expected on either parent process for some time afterward, as each new instance of baby sends inter-
       mittent signals to the parent processes which must be handled by the parents immediately.

       A baby process will frequently dump core, requiring either or both parent processes to clean up after it.

       Despite the reams of available documentation on invoking and maintaining baby, most parent processes are overwhelmed.

AUTHORS

       From a man page by Joe Beck, <beck@cs.ualberta.ca>.

																	   BABY(1)

FORK(2) 						      BSD System Calls Manual							   FORK(2)

NAME

     fork -- create a new process

SYNOPSIS

     #include <unistd.h>

     pid_t
     fork(void);

DESCRIPTION

     Fork() causes creation of a new process.  The new process (child process) is an exact copy of the calling process (parent process) except for
     the following:

	   o   The child process has a unique process ID.

	   o   The child process has a different parent process ID (i.e., the process ID of the parent process).

	   o   The child process has its own copy of the parent's descriptors.	These descriptors reference the same underlying objects, so that,
	       for instance, file pointers in file objects are shared between the child and the parent, so that an lseek(2) on a descriptor in the
	       child process can affect a subsequent read or write by the parent.  This descriptor copying is also used by the shell to establish
	       standard input and output for newly created processes as well as to set up pipes.

	   o   The child processes resource utilizations are set to 0; see setrlimit(2).

RETURN VALUES

     Upon successful completion, fork() returns a value of 0 to the child process and returns the process ID of the child process to the parent
     process.  Otherwise, a value of -1 is returned to the parent process, no child process is created, and the global variable errno is set to
     indicate the error.

ERRORS

     Fork() will fail and no child process will be created if:

     [EAGAIN]		The system-imposed limit on the total number of processes under execution would be exceeded.  This limit is configuration-
			dependent.

     [EAGAIN]		The system-imposed limit MAXUPRC (<sys/param.h>) on the total number of processes under execution by a single user would
			be exceeded.

     [ENOMEM]		There is insufficient swap space for the new process.

LEGACY SYNOPSIS

     #include <sys/types.h>
     #include <unistd.h>

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

SEE ALSO

     execve(2), sigaction(2), wait(2), compat(5)

HISTORY

     A fork() function call appeared in Version 6 AT&T UNIX.

CAVEATS

     There are limits to what you can do in the child process.	To be totally safe you should restrict yourself to only executing async-signal
     safe operations until such time as one of the exec functions is called.  All APIs, including global data symbols, in any framework or library
     should be assumed to be unsafe after a fork() unless explicitly documented to be safe or async-signal safe.  If you need to use these frame-
     works in the child process, you must exec.  In this situation it is reasonable to exec yourself.

4th Berkeley Distribution					   June 4, 1993 					 4th Berkeley Distribution