On Tue, May 30, 2006 at 12:08:45PM +0530, Gopala Krishna wrote: > Good evening/morning/afternoon, > > I knew a process ID which creates a pocess, which inturn creates a process, > which in turn creates another process (like this down the line for about 10 > process). Now I want to see what are all the process created down th line from > the pid of the first process. Is there any way/scheme to find it out. > > Please let me know. > > Thanks and regards, > GOpal. Hmm, it's an interesting question. In fact, you want to look at the tree from the bottom to the top. You cant the pid of the parent (with getppid()), but how can you get the grand parent process ? One idea is to implement a signal handler which executes the function getppid() on the parent : then you can get the pid of the grand parent. But since the parent of a process is often a shell instance, it's not acceptable (you won't modify the shell code !:)) Well in fact, you have to access the process table structure : but from user space, I guess it's impossible. Fortunately, here comes the proc filesystem ! So, you have the pid of the father process : look at the file /proc/'ppid'/status there should be a fild ppid : you have the pid of your grand parent. You can do a recursive function to find all the ancestors of your process. This solution is quite annoying since you have to handle files, but it works. If this solution is not acceptable for you, you can look at the pstree source code. I don't know if you wanted to do that in your own programm or just wanted some soft to give you the entire tree (like pstree). Anyway... :) -- tyler tyler@xxxxxxxx ___________________________________________________________________________ Yahoo! Mail réinvente le mail ! Découvrez le nouveau Yahoo! Mail et son interface révolutionnaire. http://fr.mail.yahoo.com -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
