<p>which compiling a multithreaded program we use gcc like below:</p> <pre class="prettyprint"><code>gcc -lpthread -D_REENTRANT -o someprogram someprogram.c </code></pre> <p>what exactly is the flag <code>-D_REENTRANT</code> doing over here?</p>

What is the _REENTRANT flag?

which compiling a multithreaded program we use gcc like below:

gcc -lpthread -D_REENTRANT -o someprogram someprogram.c

what exactly is the flag -D_REENTRANT doing over here?

932

asked Apr 08 '10 16:04

Defining _REENTRANT causes the compiler to use thread safe (i.e. re-entrant) versions of several functions in the C library.

You can search your header files to see what happens when it's defined.

117

answered Oct 04 '22 11:10

If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!