Sponsored Content
Top Forums Programming How to find if a process a daemon ? Post 302212560 by vino on Monday 7th of July 2008 10:06:53 PM
Old 07-07-2008
How to find if a process a daemon ?

I have a scenario where I need to find if a process is a daemon process or not. This check needs to be done from within the process. I know there are no direct API's to do so. I have explored these options.

1. ctermid() - this can be unsuccessful as per the man pages
2. int devtty; if ((devtty = open ("/dev/tty", O_RDWR)) < 0) then it is a daemon. Are there any other cases, where this may not be true ?
3. Since setsid() is used to detach from a terminal, perhaps getsid() can be used to check for process group leader and session leader.
4. Look if parent pid is 1 or not. Can a daemon process have a ppid other than 1 ?

Are there more options ? I dont know if there is a best way to do this, but what would be the most appropriate way ?
 

10 More Discussions You Might Find Interesting

1. Programming

Daemon process

Hi, I have to write a daemon process, which performs certain operations in the background. Now since it performs operations in the background, it should not display anything to the standard output. The problem is that it still displays, text on standard output. Can anyone tell me (it is... (2 Replies)
Discussion started by: s_chordia
2 Replies

2. Programming

What is a daemon process?

This is gonna seem really silly to almost evryone here - but I need to know : what is a daemon process? Thanks (6 Replies)
Discussion started by: Kanu77
6 Replies

3. UNIX for Advanced & Expert Users

zombie daemon process!!

My daemon process is the child of init and init has the responsibility to remove it, once it turns zombie. But I want to ask why the daemon process which is child of init turns zombie in the first place. What measures I have to take to avoid this? rish (1 Reply)
Discussion started by: rish2005
1 Replies

4. Linux

daemon process

how i will write the daemon process,if any body have sample daemon process send me. (1 Reply)
Discussion started by: suresh_rupineni
1 Replies

5. Shell Programming and Scripting

How to starting process as daemon using ssh command?

Hello, I need to run a command on remote Linux using the ssh command from my local machine. I am able to execute the command on remote machine using ssh but it's behaving strangely. The command is supposed to start a daemon process on remote linux box and the control should return back to me... (5 Replies)
Discussion started by: nitinshukla
5 Replies

6. UNIX for Dummies Questions & Answers

How to write Pro*C daemon process using multithreading?

Hello, I am new to this forum and this is my first post here... I have never worked on either Pro*C or Multithreading..Now, i have to write a Pro*C, Multithreading daemon process.. I dont know where to start.. Can anybody help me with examples? 1. need to write a Pro*C multithreading... (0 Replies)
Discussion started by: kachiraju
0 Replies

7. Shell Programming and Scripting

Diff between Bg and daemon process

Dear Unix Gurus, Plz provide major diff between background process and daemon process. Is it control available for daemon process?. (3 Replies)
Discussion started by: kkl
3 Replies

8. Shell Programming and Scripting

run this script as a daemon process

Hi, HI , I have a simple script that moves files from one folder to another folder, I have already done the open-ssh server settings and the script is working fine and is able to transfer the files from one folder to another but right now I myself execute this script by using my creditianls to... (3 Replies)
Discussion started by: nks342
3 Replies

9. UNIX for Dummies Questions & Answers

Oracle process running as user daemon

Hi, When process listing, I came across a process running as user daemon. daemon 23576 23574 0 07:32:04 ? 0:07 oracle (DESCRIPTION=(LOCAL=YES)(ADDRESS=(PROTOCOL=beq))) root 27526 27444 1 07:38:43 ttyp5 0:00 grep 23574 why a process runs as user daemon, when it should be... (3 Replies)
Discussion started by: wilsonee
3 Replies

10. Programming

Daemon process

I wish to make a process run in the background, but only one instance of it, and not many, so when the program is loaded, it has to check whether another instance of the same program is running and if so to exit. How do I do this ? (4 Replies)
Discussion started by: sundaresh
4 Replies
setsid(2)							System Calls Manual							 setsid(2)

NAME
setsid - Sets the process group ID SYNOPSIS
#include <unistd.h> pid_t setsid( void ); Application developers may want to specify an #include statement for <sys/types.h> before the one for <unistd.h> if programs are being developed for multiple platforms. The additional #include statement is not required on Tru64 UNIX systems or by ISO or X/Open standards, but may be required on other vendors' systems that conform to these standards. STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: setsid(): XPG4, XPG4-UNIX Refer to the standards(5) reference page for more information about industry standards and associated tags. DESCRIPTION
The setsid() function creates a new session when the calling process is not a process group leader. The calling process then becomes the session leader of this session, becomes the process leader of the new process group, and has no controlling terminal. The process group ID of the calling process is set equal to its process ID. The calling process becomes the only process in the new process group and the only process in the new session. RETURN VALUES
Upon successful completion, the setsid function returns the value of the new process group ID. Otherwise, a value of (pid_t)-1 is returned and errno is set to indicate the error. ERRORS
The setsid() function sets errno to the specified values for the following conditions: The calling process is already the process group leader, or the process group ID of another process matches the process ID of the calling process. RELATED INFORMATION
Functions: getpid(2), getsid(2), setpgid(2) Standards: standards(5) delim off setsid(2)
All times are GMT -4. The time now is 06:29 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy