your code would be more easily readable with tabs , to get them use the
[code]
code here
[/code]
this will look like this:
Anyway, it seems as though you are entering an infinite while loop "polling" the shared memory for a change in the child. Then you are writing back to the shared memory in said child for another to pick it up. This is all being done without any semaphore protection and therefore it is possible that things could go awry.
At any rate, this polling makes inefficient use of the CPU cycles, IMO. While it gets your assignment done...I just wanted to point out that its probably not an effective way of doing it.
However, it looks like you got it done...congrats.
edit: looks like the child does the shared memory write...this is worse yet.
Last edited by DreamWarrior; 04-19-2004 at 03:35 PM..
Dear all,
suppose that I start a process (named "father"). "father" starts in turns a process called "child" with an execv call (after a fork). In this way "father" will be notified if "chlid" crashes (SIGCHILD mechanism). The problem is:
if "father" crashes, how can I do to be recreate a... (1 Reply)
I don't follow what these are...
this is what my text says...
"When a process is started, a duplicate of that process is created. This new process is called the child and the process that created it is called the parent. The child process then replaces the copy for the code the parent... (1 Reply)
Hello.
I have a global function name func1() that I am sourcing in from script A. I call the function from script B. Is there a way to find out which script called func1() dynamically so that the func1() can report it in the event there are errors?
Thanks (2 Replies)
Hello,
How many child processes are actually created when running this code ?
#include <signal.h>
#include <stdio.h>
int main () {
int i ;
setpgrp () ;
for (i = 0; i < 10; i++) {
if (fork () == 0) {
if ( i & 1 ) setpgrp () ;
printf ("Child id: %2d, group: %2d\n", getpid(),... (0 Replies)
Hello,
How many child processes are actually created when running this code ?
#include <signal.h>
#include <stdio.h>
int main () {
int i ;
setpgrp () ;
for (i = 0; i < 10; i++) {
if (fork () == 0) {
if ( i & 1 ) setpgrp () ;
printf ("Child id: %2d, group: %2d\n",... (1 Reply)
All,
Ok...so I know I *should* be able to control a process's stdin and stdout from the parent by creating pipes and then dup'ing them in the child. And, this works with all "normal" programs that I've tried. Unfortunately, I want to intercept the stdin/out of the scp application and it seems... (9 Replies)
I have a .NET application that remotely starts, stops, and gets status of Windows services and scheduled tasks. I would like to add the capability of starting, stopping, and getting status of remote AIX applications also. Based on some preliminary research, one option may be to use 3rd party .NET... (0 Replies)
I am trying to implement the below using Ksh script on a Lx machine.
There is a file(input_file) with 100K records. For each of these records, certain script(process_rec) needs to be called with the record as input. Sequential processing is time-consuming and parallel processing would eat up... (2 Replies)
is there a universal way of getting the children of a particular process? i'm looking for a solution that works across different OSes...linux, aix, sunos, hpux.
i did a search online and i kept finding answers that were specific to Linux..i.e. pstree.
i want to be able to specify a process... (2 Replies)
Discussion started by: SkySmart
2 Replies
LEARN ABOUT XFREE86
renice
RENICE(1) User Commands RENICE(1)NAME
renice - alter priority of running processes
SYNOPSIS
renice [-n] priority [-g|-p|-u] identifier...
DESCRIPTION
renice alters the scheduling priority of one or more running processes. The first argument is the priority value to be used. The other
arguments are interpreted as process IDs (by default), process group IDs, user IDs, or user names. renice'ing a process group causes all
processes in the process group to have their scheduling priority altered. renice'ing a user causes all processes owned by the user to have
their scheduling priority altered.
OPTIONS -n, --priority priority
Specify the scheduling priority to be used for the process, process group, or user. Use of the option -n or --priority is optional,
but when used it must be the first argument.
-g, --pgrp
Interpret the succeeding arguments as process group IDs.
-p, --pid
Interpret the succeeding arguments as process IDs (the default).
-u, --user
Interpret the succeeding arguments as usernames or UIDs.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
EXAMPLES
The following command would change the priority of the processes with PIDs 987 and 32, plus all processes owned by the users daemon and
root:
renice +1 987 -u daemon root -p 32
NOTES
Users other than the superuser may only alter the priority of processes they own. Furthermore, an unprivileged user can only increase the
``nice value'' (i.e., choose a lower priority) and such changes are irreversible unless (since Linux 2.6.12) the user has a suitable
``nice'' resource limit (see ulimit(1) and getrlimit(2)).
The superuser may alter the priority of any process and set the priority to any value in the range -20 to 19. Useful priorities are: 19
(the affected processes will run only when nothing else in the system wants to), 0 (the ``base'' scheduling priority), anything negative
(to make things go very fast).
FILES
/etc/passwd
to map user names to user IDs
SEE ALSO nice(1), getpriority(2), setpriority(2), credentials(7), sched(7)HISTORY
The renice command appeared in 4.0BSD.
AVAILABILITY
The renice command is part of the util-linux package and is available from Linux Kernel Archive <https://www.kernel.org/pub/linux/utils
/util-linux/>.
util-linux July 2014 RENICE(1)