BPX1LSK (lseek) example

The following code changes the file (FILEDESC) offset to 80 bytes past the current offset. For the callable service, see lseek (BPX1LSK, BPX4LSK) — Change a file's offset. For the data structure, see BPXYSEEK — Constants for lseek. AMODE 64 callers use BPX4LSK (lseek) example.

                                              
       MVC   FILEDESC,..           File descriptor from open          34
         MVC   OFFSET(08),=FL8'80'   Forward 80 Bytes                   
         MVC   REFPT,=A(SEEK_CUR)    Current offset of the file         
         SPACE ,                                                        
         CALL  BPX1LSK,              Change a file's offset            +
               (FILEDESC,            File descriptor                   +
               OFFSET,               I/O: Offset in file               +
               REFPT,                Input: Reference point, BPXYSEEK  +
               RETVAL,               Return value: 0 or -1             +
               RETCODE,              Return code                       +
               RSNCODE),             Reason code                       +
               VL,MF=(E,PLIST)       ----------------------------------