I believe many years ago, like
around 15 years ago, you were
working on a C library for CMS,
and maybe also MVS.
I'm not sure anything was ever
released. Would it be possible
for you to package up your work
and release it (including either
a PD notice or whatever your
copyright restrictions are) just
The only open source C libraries
for the IBM mainframe (any operating
system) that I know of are:
which may open up the possibility of
using the S/390 (not i370) target of
GCC 4 (not GCC 3.4.6 and lower)
to produce 31-bit and 64-bit load
modules that run on z/OS and MVS/380.
GNU Cobol is probably dependent
on GCC 4 working too.
Not sure if Waterloo C for MUSIC/SP
provides runtime source.
Also not sure if the C compiler that
comes with MTS (called "c89") has
open source runtime.
I don't know if the C compiler ported
to MVS by Dennis Ritchie and co in
the 1970s was ever released.
I think Open Watcom contains some
code regarding an MVS target, but
I don't think it is operational any
more, and I don't think there was a
mainframe C library either.