This directory contains the sources of the GNU C Library. See the file "version.h" for what release version you have.

The GNU C Library is the standard system C library for all GNU systems, and is an important part of what makes up a GNU system. It provides the system API for all programs written in C and C-compatible languages such as C++ and Objective C; the runtime facilities of other programming languages use the C library to access the underlying operating system.

In GNU/Linux systems, the C library works with the Linux kernel to implement the operating system behavior seen by user applications. In GNU/Hurd systems, it works with a microkernel and Hurd servers.

The GNU C Library implements much of the POSIX.1 functionality in the GNU/Hurd system, using configurations i[4567]86-*-gnu and x86_64-gnu.

When working with Linux kernels, this version of the GNU C Library requires Linux kernel version 3.2 or later.

Also note that the shared version of the libgcc_s library must be installed for the pthread library to work correctly.

The GNU C Library supports these configurations for using Linux kernels:

aarch64*-*-linux-gnu
alpha*-*-linux-gnu
arc*-*-linux-gnu
arm-*-linux-gnueabi
csky-*-linux-gnuabiv2
hppa-*-linux-gnu
i[4567]86-*-linux-gnu
x86_64-*-linux-gnu  Can build either x86_64 or x32
loongarch64-*-linux-gnu Hardware floating point, LE only.
m68k-*-linux-gnu
microblaze*-*-linux-gnu
mips-*-linux-gnu
mips64-*-linux-gnu
or1k-*-linux-gnu
powerpc-*-linux-gnu Hardware or software floating point, BE only.
powerpc64*-*-linux-gnu  Big-endian and little-endian.
s390-*-linux-gnu
s390x-*-linux-gnu
riscv32-*-linux-gnu
riscv64-*-linux-gnu
sh[34]-*-linux-gnu
sparc*-*-linux-gnu
sparc64*-*-linux-gnu

If you are interested in doing a port, please contact the glibc maintainers; see https://www.gnu.org/software/libc/ for more information.

See the file INSTALL to find out how to configure, build, and install the GNU C Library. You might also consider reading the WWW pages for the C library at https://www.gnu.org/software/libc/.

The GNU C Library is (almost) completely documented by the Texinfo manual found in the manual/' subdirectory. The manual is still being updated and contains some known errors and omissions; we regret that we do not have the resources to work on the manual as much as we would like. For corrections to the manual, please file a bug in themanual' component, following the bug-reporting instructions below. Please be sure to check the manual in the current development sources to see if your problem has already been corrected.

Please see https://www.gnu.org/software/libc/bugs.html for bug reporting information. We are now using the Bugzilla system to track all bug reports. This web page gives detailed information on how to report bugs properly.

The GNU C Library is free software. See the file COPYING.LIB for copying conditions, and LICENSES for notices about a few contributions that require these additional notices to be distributed. License copyright years may be listed using range notation, e.g., 1996-2015, indicating that every year in the range, inclusive, is a copyrightable year that would otherwise be listed individually.