BPX4MMP (mmap) example

The following code changes the protection of a memory mapped area. For the callable service, see mmap (BPX1MMP, BPX4MMP) — Map pages of memory. AMODE 31 callers use BPX1MMP (mmap) example.

                                              
       MVC   FILEDESC,..           File descriptor                      
         SPACE ,                                                        
         CALL  BPX4MMP,              map pages of memory               +
               (MAP_ADDRESS,         Input: address of mapped area     +
               MAP_LENGTH,           Input: area length                +
               =A(MAP_PRIVATE),      Input: Map type                   +
               FILEDESC,             Input: File descriptor            +
               =AD(0),               Input: File offset                +
               RETURNEDADDRESS,      Output:  value mapped address     +
               RETVAL,               Return value: 0 or -1             +
               RETCODE,              Return code                       +
               RSNCODE),             Reason code                       +
               MF=(E,PLIST)          ----------------------------------