Q: I looked in my info/ subdirectory, but I can't find docs
for some of the utilities, like SED or GPROF.
Q: STL, the C++ Standard Template Library, seems to be
undocumented....
A: SED and GPROF are documented in the latest GNU
releases, v2gnu/sed302b.zip and
v2gnu/bnu281b.zip. Download the latest releases,
and you will get the missing docs.
The STL documentation is not included in the GNU GCC distribution (it appears that nobody has bothered to write a free documentation for it). But you can find the STL docs on the net; this includes the full documentation and a tutorial. Many books that describe C++ programming also include documentation of large parts of the STL. Another place to look for the reference material about C++ language and classes is the Dinkumware site. (Dinkumware is a company founded by P.J. Plauger, one of the world's leading experts on C++ and the STL, which produces the C++ library used by the MSVC compiler.)
The ANSI organization is selling the official ANSI C++ Standard (full document, about 800 pages) for $18 in PDF format.
If you have some other package without any docs, try downloading the
source archive (*s.zip) for that package and look inside it,
usually in the directory called man/ or doc/. Omitting
documentation from the binary (*b.zip) distribution is generally
considered a bug, so if you find the docs in source distribution only,
please report these cases on the comp.os.msdos.djgpp news group, so that next
binary release could fix this.