Overview Any Unix-like operating system needs a C library: the library which defines the "system calls" and other basic facilities such as open, malloc, printf, exit... The GNU C Library is used as the C library in the GNU systems and most systems with the Linux kernel. Project Goals The GNU C Library is primarily designed to be a portable and high performance C library. It follows all relevant standards including ISO C11 and POSIX.1-2008. It is also internationalized and has one of the most complete internationalization interfaces known. Site: http://www.gnu.org/software/libc/