ⓘ Execute Channel Program. In IBM mainframe operating systems, Execute Channel Program is a supervisor call for low-level device access, where the programmer is r ..

                                     

ⓘ Execute Channel Program

In IBM mainframe operating systems, Execute Channel Program is a supervisor call for low-level device access, where the programmer is responsible for providing a channel program - a list of device-specific commands - to be executed by I/O channels, control units and devices. EXCP for OS/360 and successors is more specifically described in the OS System Programmers Guide., EXCP for DOS/360 and successors is more specifically described in DOS Supervisor and I/O Macros. This article mostly reflects OS/360 through, some details are different for TOS/360 and DOS/360 through z/VSE.