Sponsored Content
Homework and Emergencies Emergency UNIX and Linux Support signal between parent process and child process Post 302546819 by hergp on Friday 12th of August 2011 08:40:51 AM
Old 08-12-2011
Just in case your problem isn't solved yet:

If you want to isolate a child process from signals to the parent, you have to use setpgrp to create a new process group, like:

Code:
pid_t pid = fork();

if (0 == pid) // child process
{
     setpgrp();
     execvp ...;
}

This way, a SIGINT or SIGHUP to the parent process won't reach the child anymore.
This User Gave Thanks to hergp For This Post:
 

10 More Discussions You Might Find Interesting

1. Programming

parent and child process question?

Hi everybody, I'm trying to understand how a parent and child processes interact. This function( below) basically measures the fork time from the perspective of the parent only. what i would like to know is how to measure the time from the perspective of parent and child (ie: inserting... (0 Replies)
Discussion started by: tosa
0 Replies

2. UNIX for Advanced & Expert Users

catch SIGCHLD signal in parent process

I want to catch SIGCHLD signal in parent process. I can't use wait() system call to catch SIGCHLD according to project requirment. Operating system linux 3.1 can any one have a solution for this. Thanking you, ranjan (2 Replies)
Discussion started by: ranjan
2 Replies

3. Programming

catching a signal from child process

i am creating children processes using fork system call every child i create goes to sleep for random time. when child stops running how can i catch his signal and turminate the child (2 Replies)
Discussion started by: emil2006
2 Replies

4. Shell Programming and Scripting

How to make the parent process to wait for the child process

Hi All, I have two ksh script. 1st script calls the 2nd script and the second script calls an 'C' program. I want 1st script to wait until the 'C' program completes. I cant able to get the process id for the 'C' program (child process) to make the 1st script to wait for the second... (7 Replies)
Discussion started by: sennidurai
7 Replies

5. UNIX for Dummies Questions & Answers

Sending signal from child to parent process!

Hi All, I facing a problem in handling signals between parent process communication. I am trying to send a signal(SIGINT) from child to parent. I am using kill function to do so and I am trying to read the signal using sigaction(). But the program is ending abruptly and I am not able to figure out... (4 Replies)
Discussion started by: vkn_1985
4 Replies

6. Shell Programming and Scripting

[KSH/Bash] Starting a parent process from a child process?

Hey all, I need to launch a script from within 2 other scripts that can run independently of the two parent scripts... Im having a hard time doing this, if anyone knows how please let me know. More detail. ScriptA (bash), ScriptB (ksh), ScriptC (bash) ScriptA, launches ScriptB ScirptB,... (7 Replies)
Discussion started by: trey85stang
7 Replies

7. Programming

how can i make that a process child send a signal?

I'm trying to do a program that makes activate an signal (SINGALARM) when the next child of a son appears but this not works. I have to caught the next child o the other (pid), to send a singnal which inform a menssage. It's anything worng in the code? thanks. the code: #include... (2 Replies)
Discussion started by: marmaster
2 Replies

8. Programming

Parent process starts before the child using signal, in C

Hi, i want that the parent process start before the child, this code doesn't work, if the child start before the parent it wait for signal, then the father send the signal SIGALRM and the child catch it and call printf; else the father call printf and send the signal to the child that call its... (1 Reply)
Discussion started by: blob84
1 Replies

9. Shell Programming and Scripting

forking a child process and kill its parent to show that child process has init() as its parent

Hi everyone i am very new to linux , working on bash shell. I am trying to solve the given problem 1. Create a process and then create children using fork 2. Check the Status of the application for successful running. 3. Kill all the process(threads) except parent and first child... (2 Replies)
Discussion started by: vizz_k
2 Replies

10. Shell Programming and Scripting

How make parent to wait from child process?

Hi all, I am starting mgen5 for sometime depends on input from a file, in a child process. now I want to make parent to wait in this child process till mgen5 finishes, or timeout happens. could anyone please tell me how to make parent to wait in child process in shell script? thanks... (2 Replies)
Discussion started by: girijajoshi
2 Replies
SETPGID(2)						      BSD System Calls Manual							SETPGID(2)

NAME
setpgid, setpgrp -- set process group SYNOPSIS
#include <unistd.h> int setpgid(pid_t pid, pid_t pgid); pid_t setpgrp(void); DESCRIPTION
Setpgid() sets the process group of the specified process pid to the specified pgid. If pid is zero, then the call applies to the current process. If the invoker is not the super-user, then the affected process must have the same effective user-id as the invoker or be a descendant of the invoking process. If the calling process is not already a session leader, setpgrp() sets the process group ID of the calling process to that of the calling process. Any new session that this creates will have no controlling terminal. RETURN VALUES
Setpgid() returns 0 when the operation was successful. If the request failed, -1 is returned and the global variable errno indicates the reason. ERRORS
Setpgid() will fail and the process group will not be altered if: [EACCES] The value of the pid argument matches the process ID of a child process of the calling process, and the child process has successfully executed one of the exec functions. [EINVAL] The value of the pgid argument is less than 0 or is not a value supported by the implementation. [EPERM] The process indicated by the pid argument is a session leader. [EPERM] The effective user ID of the requested process is different from that of the caller and the process is not a descendant of the calling process. [EPERM] The value of the pgid argument is valid, but does not match the process ID of the process indicated by the pid argument and there is no process with a process group ID that matches the value of the pgid argument in the same session as the calling process. [ESRCH] The value of the pid argument does not match the process ID of the calling process or of a child process of the calling process. LEGACY SYNOPSIS
#include <unistd.h> int setpgrp(pid_t pid, pid_t pgid); The legacy setpgrp() function is a clone of the setpgid() function, retained for calling convention compatibility with historical versions of BSD. COMPATIBILITY
Use of the legacy version of the setpgrp() call will cause compiler diagnostics. Use setpgid() instead. Use of private (and conflicting) prototypes for setpgrp() will cause compiler diagnostics. Delete the private prototypes and include <unistd.h>. SEE ALSO
getpgrp(2), compat(5) STANDARDS
The setpgid() function conforms to IEEE Std 1003.1-1988 (``POSIX.1''). 4th Berkeley Distribution June 4, 1993 4th Berkeley Distribution
All times are GMT -4. The time now is 05:38 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy