I want to know if a process on my computer exists. There are three ways to test this through code in C: kill, getpid (pid) ,stat (path, & stat)
I want to know what are the pros and cons of each method?
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By stat do you mean checking for `/proc/
`? – Barmar Aug 03 '20 at 15:49 -
Uhm... `getpid()` doesn't take a parameter – Marco Aug 03 '20 at 15:49
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1Does this answer your question? [Check if process exists given its pid](https://stackoverflow.com/questions/9152979/check-if-process-exists-given-its-pid) – Marco Aug 03 '20 at 15:51
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The `getpid()` function tells you the PID of the current process. You know the current process exists – if it didn't, it couldn't execute `getpid()` (or any other function). – Jonathan Leffler Aug 04 '20 at 03:48
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kill(pid, 0) is POSIX compliant whereas stat("/proc/<pid>", ...) is not.
I don't know what you mean with getpid() as it doesn't take any parameters.
Update:
getpgid(pid) is POSIX compliant as well, so I don't think there's a difference between using kill and getpgid for your purpose. I would choose kill because it's more widely used.
Marco
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ok.. but getpid(
) <0 if true, the process is not alive. what the adventeges and disadventeges? – Netanel Shimoni Aug 04 '20 at 12:02 -
`getpid()` returns the process ID of the **current** process. It doesn't check if any other process is running. – Marco Aug 04 '20 at 14:12
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