2.2 Compiling and Linking

The library header files are installed in their own ‘gsl’ directory. You should write any preprocessor include statements with a ‘gsl/’ directory prefix thus,

#include <gsl/gsl_math.h>

If the directory is not installed on the standard search path of your compiler you will also need to provide its location to the preprocessor as a command line flag. The default location of the ‘gsl’ directory is ‘/usr/local/include/gsl’. A typical compilation command for a source file ‘example.c’ with the GNU C compiler gcc is,

$ gcc -Wall -I/usr/local/include -c example.c

This results in an object file ‘example.o’. The default include path for gcc searches ‘/usr/local/include’ automatically so the -I option can actually be omitted when GSL is installed in its default location.