Before you do anything else, you should read the file FAQ found at the top level of the source tree. This file answers common questions and describes problems you may experience with compilation and installation. It is updated more frequently than this manual.
Features can be added to GNU Libc via add-on bundles. These are
separate tarfiles which you unpack into the top level of the source
tree. Then you give
configure the `--enable-add-ons' option
to activate them, and they will be compiled into the library. As of the
2.2 release, one important component of glibc is distributed as
“official” add-ons: the linuxthreads add-on. Unless you are doing an
unusual installation, you should get this.
Support for POSIX threads is maintained by someone else, so it's in a separate package. It is only available for Linux systems, but this will change in the future. Get it from the same place you got the main bundle; the file is glibc-linuxthreads-VERSION.tar.gz.
You will need recent versions of several GNU tools: definitely GCC and GNU Make, and possibly others. See Tools for Compilation, below.