MVS Jan 2005.p65 - CBT Tape

something like:
pid = fork();
if (pid < Ø)
{
printf("fork() failed – errno=%d\n",errno);
return(-1);
}
else if (pid > Ø)
{
printf("Executing in the parent process. Child PID is %d\n",pid);
}
else
{
printf("Executing in the child process.\n");
}
The fork() function call has the following drawbacks:
It can be used only in programs running in problem state,
key 8.
The child process runs in a separate address space from
that of the parent process.
The parent process task issuing the fork() is copied into
the child address space.
MVS files opened in the parent process are not opened in
the child process with the exception of TASKLIB, STEPLIB,
and/or JOBLIB. The child process maintains the same
MVS program search order as the initiating parent process,
but does not maintain access to other MVS datasets
allocated to the parent process.
THE SPAWN() FUNCTION
A second multi-tasking method is the spawn() function. Here
are some of its functional highlights:
The child process will inherit the parent process’s TASKLIB,
STEPLIB, and JOBLIB allocations unless a STEPLIB
environment variable is used for the spawned process.
The setting of the _BPX_SHAREAS environment variable
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