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Top Forums Programming Fork and then exec problem with signals Post 302460591 by achenle on Thursday 7th of October 2010 05:52:37 AM
Old 10-07-2010
Are execl(), printf(), and sleep() all async-signal safe?

I don't think execl() is, and I'd bet a lot that printf() isn't, and whether or not sleep() is async-signal safe probably depends on the implementation.

And FWIW, the custom signal-handler will not propagate across any of the exec()-type calls:

Quote:
execve() does not return on success, and the text, data, bss, and stack of the calling process are overwritten by that of the program loaded. The program invoked inherits the calling process's PID, and any open file descriptors that are not set to close-on-exec. Signals pending on the calling process are cleared. Any signals set to be caught by the calling process are reset to their default behaviour. The SIGCHLD signal (when set to SIG_IGN) may or may not be reset to SIG_DFL.
 

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