If you want to code in C on MVS (3.8 thru z/OS), there is now another option available, and it is both free and clear of copyright conditions. A CMS port is provided also.

There are two separate parts to this, GCC and PDPCLIB. They are different products, written by different people, and with different licencing restrictions.

You can actually potentially mix and match these two things. E.g. GCC could be used with a different C runtime library other than PDPCLIB. PDPCLIB could be used with a C compiler other than GCC (indeed, it was originally written for use with C/370, to produce stand-alone executables, which aren't able to be produced natively). The only combination that works "out of the box" currently though, is GCC combined with PDPCLIB. This combination is referred to from now on as "GCCMVS".

The AWS Tape and XMIT file downloads contain the following libraries: