Assembler and C-language facilities for writing a PFS in C

This appendix contains assembler routines that can be useful for writing a PFS in C.

Replacements for the C/370™ Systems Programming Facilities routines @@XGET and @@XFREE are included. These routines must be included in your PFS. They are supplied in the BPXFASM sample, included here, which must be assembled and link-edited with all PFS load modules.

C-function prototypes and assembler routines are also included for the following facilities:

BPXT4KGT: Allocate a page of storage
BPXT4KFR: Free a page of storage
BPXTWAIT: Wait on an ECB list
BPXTPOST: Post an ECB
BPXTEPOC: Convert time-of-day clock format to seconds-since-the-epoch