12-12-2011
Yes, that's it. exec() replaces your current program. You have to fork, whether you want it in the foreground or not. Just wait() for processes to finish if they're in the "foreground".
There's more to fg vs bg than just waiting, there's also things to do with terminal control I'm I'm only barely aware of. If I can't find the right man page, hopefully someone can fill us in.
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LEARN ABOUT SUSE
tcsetpgrp
TCGETPGRP(3) Linux Programmer's Manual TCGETPGRP(3)
NAME
tcgetpgrp, tcsetpgrp - get and set terminal foreground process group
SYNOPSIS
#include <unistd.h>
pid_t tcgetpgrp(int fd);
int tcsetpgrp(int fd, pid_t pgrp);
DESCRIPTION
The function tcgetpgrp() returns the process group ID of the foreground process group on the terminal associated to fd, which must be the
controlling terminal of the calling process.
The function tcsetpgrp() makes the process group with process group ID pgrp the foreground process group on the terminal associated to fd,
which must be the controlling terminal of the calling process, and still be associated with its session. Moreover, pgrp must be a
(nonempty) process group belonging to the same session as the calling process.
If tcsetpgrp() is called by a member of a background process group in its session, and the calling process is not blocking or ignoring
SIGTTOU, a SIGTTOU signal is sent to all members of this background process group.
RETURN VALUE
When fd refers to the controlling terminal of the calling process, the function tcgetpgrp() will return the foreground process group ID of
that terminal if there is one, and some value larger than 1 that is not presently a process group ID otherwise. When fd does not refer to
the controlling terminal of the calling process, -1 is returned, and errno is set appropriately.
When successful, tcsetpgrp() returns 0. Otherwise, it returns -1, and errno is set appropriately.
ERRORS
EBADF fd is not a valid file descriptor.
EINVAL pgrp has an unsupported value.
ENOTTY The calling process does not have a controlling terminal, or it has one but it is not described by fd, or, for tcsetpgrp(), this
controlling terminal is no longer associated with the session of the calling process.
EPERM pgrp has a supported value, but is not the process group ID of a process in the same session as the calling process.
CONFORMING TO
POSIX.1-2001.
NOTES
These functions are implemented via the TIOCGPGRP and TIOCSPGRP ioctls.
History
The ioctls appeared in 4.2BSD. The functions are POSIX inventions.
SEE ALSO
setpgid(2), setsid(2), credentials(7)
COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU
2003-01-28 TCGETPGRP(3)