Re: will system() waste memory?

Bin Chen <binary.chen@xxxxxxxxx> wrote:
Most call to system() is to run a brand new program but I want to know
if the parent run system() after allocated a large memory, will the
memory duplicated to the systemed program which is unnecessary?

If so, how can I do to avoid the wasted memory?

For this reason posix_spawn() has been introduced:

http://www.opengroup.org/onlinepubs/009695399/functions/posix_spawn.html

See the discussion in the "Rationale" section.

You can assume system() uses the optimal implementation available on your
platform. system() might succeed in some cases where fork() + exec() would
fail.


--
Daniel
.

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