set process group
Standard C Library (libc, -lc)
() system call sets the process
group of the specified process pid
is zero, then the call applies to the
current process. If pgrp
is zero, then the
process id of the process specified by pid
If the affected process is not the invoking process, then it must be a child of
the invoking process, it must not have performed an
operation, and both processes must be in
the same session. The requested process group ID must already exist in the
session of the caller, or it must be equal to the target process ID.
() function returns the
value 0 if successful; otherwise the value -1 is returned and
the global variable errno
is set to indicate
() system call is identical to
(), and is retained for calling
convention compatibility with historical versions of
() system call will fail and the
process group will not be altered if:
- The requested process group ID is not legal.
- The requested process does not exist.
- The target process is not the calling process or a child of the calling
- The requested process is a child of the calling process, but it has
performed an exec(3) operation.
- The target process is a session leader.
- The requested process group ID is not in the session of the caller, and it
is not equal to the process ID of the target process.
() system call is expected to
conform to IEEE Std 1003.1-1990