08-26-2001
forking
Wee,
Yes you could use fork() BUT...
I would also recommend using threads to
accomplish what you are proposing. If you were
to use fork(), you would have as many separate
programs running as you have keywords per query.
Then, you would have to synchronize the results
of each into a single result. Threads will allow
you to run each keyword query against separate
databases but still allow you to synchronize
the results from within the same program. I
would recommend reading...
"Programming with POSIX Threads"
ISBN 0-201-63392-2
"Pthreads Programming"
ISBN 1-56592-115-1
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LEARN ABOUT SUSE
sched_yield
SCHED_YIELD(2) Linux Programmer's Manual SCHED_YIELD(2)
NAME
sched_yield - yield the processor
SYNOPSIS
#include <sched.h>
int sched_yield(void);
DESCRIPTION
sched_yield() causes the calling thread to relinquish the CPU. The thread is moved to the end of the queue for its static priority and a
new thread gets to run.
RETURN VALUE
On success, sched_yield() returns 0. On error, -1 is returned, and errno is set appropriately.
ERRORS
In the Linux implementation, sched_yield() always succeeds.
CONFORMING TO
POSIX.1-2001.
NOTES
If the calling thread is the only thread in the highest priority list at that time, it will continue to run after a call to sched_yield().
POSIX systems on which sched_yield() is available define _POSIX_PRIORITY_SCHEDULING in <unistd.h>.
Strategic calls to sched_yield() can improve performance by giving other threads or processes a chance to run when (heavily) contended
resources (e.g., mutexes) have been released by the caller. Avoid calling sched_yield() unnecessarily or inappropriately (e.g., when
resources needed by other schedulable threads are still held by the caller), since doing so will result in unnecessary context switches,
which will degrade system performance.
SEE ALSO
sched_setscheduler(2) for a description of Linux scheduling.
Programming for the real world - POSIX.4 by Bill O. Gallmeister, O'Reilly & Associates, Inc., ISBN 1-56592-074-0
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/.
Linux 2008-10-18 SCHED_YIELD(2)