HOW TO INSTALL - manually: 1. Read the description of macros that control the bahaviour of the program at the beginning of the file snprintf.c, change the definitions in snprintf.c or in Makefile if necessary. 2. make 3. move the file snprintf.o where your programs will find it HOW TO INSTALL - with autoconf: Contributed by Caolan McNamara : Though it might be overkill for snprintf I also have an autoconf and automaked version which works out the need for long long support and makes snprintf optionally into a dynamic library on libtool supported platforms. 1. cd with_autoconf 2. follow instructions in the file INSTALL there.