Sponsored Content
Top Forums Shell Programming and Scripting How to detect that foreground process is waiting for input? Post 302827469 by alister on Friday 28th of June 2013 07:27:59 PM
Old 06-28-2013
Quote:
Originally Posted by Corona688
Proper background process will still be able to print
Not necessarily. To successfully write to the terminal from a background process, the process group must not be orphaned and either the terminal's tostop setting must be disabled or the process must ignore SIGTTOU.

Regards,
Alister
 

10 More Discussions You Might Find Interesting

1. Linux

waiting process

how to know the information of the waiting process how to calculate the time of the process that it has taken to execute i want to make a program that Should be able to keep a log of the processes expired(The log should contain the starting time, expiry time, time slices used, total execution... (2 Replies)
Discussion started by: shukla_chanchal
2 Replies

2. UNIX for Advanced & Expert Users

Process(s) ID waiting on IO?

Hello Experts!! My CPU is waiting a lot (around 33%) on I/O. I would like to find out what process(s) are waiting on the i/o. Below is my real time output of vmstat and sar. Thanks for you help !!!! Regards Citrus OS: AIX - 5L : /u2/oracle >oslevel 5.3.0.0 : /u2/oracle... (9 Replies)
Discussion started by: Citrus143
9 Replies

3. Programming

Detecting if command is waiting for input

Hi, After doing a fork and executing a shell, we execute (third party) commands which are essentially non-interactive. But some of them ask for input, under some (unforeseeable) circumstances. When this happens we go on waiting for output. Their is timeout, of course, but we don't seem to know... (5 Replies)
Discussion started by: slash_blog
5 Replies

4. UNIX for Advanced & Expert Users

make a foreground running process to run background without hang up

I've tried this a long time ago and was successful but could not remember how i did it. Tried ctrl+Z and then used bg % could not figure what i did after to keep it no hangup - not sure if used nohup -p pid, can u plz help me out if this can be done. Any help will be appreciated. (12 Replies)
Discussion started by: pharos467
12 Replies

5. Shell Programming and Scripting

Background and Foreground of a process within a script

I'm not sure if it is even possible but I figured if it was someone here would know how to do it... I am running a script which starts a bunch of processes in the background but there is one process I would like to bring back to the foreground when complete. Unfortunately the process that I... (2 Replies)
Discussion started by: ctruhn
2 Replies

6. UNIX for Dummies Questions & Answers

bringing a process to the foreground

If i have a single file i would just press fg but if i have multiple files running in the backgound and want to bring a specific one to the foreground how would i do that? Thanks!! (1 Reply)
Discussion started by: JamieMurry
1 Replies

7. UNIX for Advanced & Expert Users

Bringing a nohup process to foreground

Hi, I have used nohup command to run a process in background. i ran successfully and i exit from that terminal. But when i login for the next time I am not able to see the process but it is working, since I am getting a e-mail alert for error issue. Please let me know how to bring that process... (3 Replies)
Discussion started by: mbguy
3 Replies

8. UNIX for Advanced & Expert Users

what is the diff b/w background and foreground process

What are all the difference between a Background and Foreground processes ?! A Background process does not have access to STDIN and OUT.. What else ? Is there any detailed description available somewhere ? (5 Replies)
Discussion started by: onequestion
5 Replies

9. Shell Programming and Scripting

How can put a background process to the foreground

Hi, guys: I am working on my own shell using c. When I put a process into the background, how can I put it back to the foreground using tcsetpgrp? Thanks (3 Replies)
Discussion started by: tomlee
3 Replies

10. UNIX for Dummies Questions & Answers

Can I convert a foreground process to NOHUP ?

OS : AIX 6.1/Solaris 10 After I started running a shell script, I've realized that it will take another 5 hours to complete. Is there anyway I could convert this foreground process to run in nohup mode so that I can go home peacefully ? I have the process ID $ ps -ef | grep... (4 Replies)
Discussion started by: kraljic
4 Replies
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. ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7). +-------------------------+---------------+---------+ |Interface | Attribute | Value | +-------------------------+---------------+---------+ |tcgetpgrp(), tcsetpgrp() | Thread safety | MT-Safe | +-------------------------+---------------+---------+ CONFORMING TO
POSIX.1-2001, POSIX.1-2008. 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 4.15 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/. GNU
2015-08-08 TCGETPGRP(3)
All times are GMT -4. The time now is 05:56 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy