Re: Can fork be used in a signal handler?

kiran <edu.mvk@xxxxxxxxx> writes:
I have a problem that i have to create a new process, when my process
gets a SIGCHLD. So i want to use fork inside the signal handler for
SIGCHLD.

Can i use like that?

Assuming there are no 'other issues' (ie 'multiple threads'), yes.
I would nevertheless rather do the fork outside the signal handler.

I know that non-reentrant functions can not be
used inside a signal handler.

This is wrong. A signal handler must only call functions which are
async-signal-safe (that's different from 'reentrant') if the signal
could have interrupted a non async-signal-safe function. A list of
those is given in the 'Signal Concepts' section of SUS.

And in the signal handler i'm traversing a linked list which has the
complexity of O(n2).

Traversing a linked-list is an operation with a linear complexity
(O(n)).
.

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