So I was trying to compile a code which has a SHA1 function .. I included following header:

#include <openssl/sha.h>

And I got the following error while compiling:

test.c:9:5: error: 'SHA1' is deprecated: first deprecated in OS X 10.7
  [-Werror,-Wdeprecated-declarations]
SHA1(msg, strlen(msg), hs);
^

But man pages still have the descriptions for that function.

Can anyone suggest any other header for a similar function ( MD5 or SHA1 )?

PS - also do I need to link any libraries while compiling using gcc?