undefined reference to `crypt'

Question

I am using the below code that i found somewhere in the net and i am getting an error when i try to build it. The compilation is ok.

Here is the error:

Answer 1

This could be due to two reasons:

1. Linking with the crypt library: use -l as a flag to gcc.
   Example: gcc ... -lcrypt where crypt.h has been compiled into a library.
2. The file crypt.h is not in the include path. You can use < and > tags around a header file only when the file is in the include path. To ensure that crypt.h is present in the include path, use the -I flag, like so: gcc ... -I ...
   Example: gcc -I./crypt where crypt.h is present in the crypt/ sub-directory of the current directory.

If you do not want to use the -I flag, change the #include to #include "crypt.h"