Re: reentrant library functions

Mike wrote:
On Sep 16, 10:01 pm, David Schwartz <dav...@xxxxxxxxxxxxx> wrote:

First, to correct one error in your post, '-lpthread' is a linker flag
and has no effect on compiling. You probably mean '-pthread', which on
many platforms (including Linux), selects compiling and linking for
pthreads support.


I do not quite understand.
My functions use semaphores to ensure that any threaded access
is exclusive (sem_wait() and sem_post()). I need the '-lpthread' flag,
or else I get linker errors.

He's saying that it's more correct to specify "-pthread" rather than "-lpthread".

Technically "-lpthread" is only a linker flag, not a compiler flag. Some platforms also require a compiler flag such as -D_REENTRANT, and if you build/link with "-pthread" it will do the right thing.

Chris
.

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