BPX1OPD (opendir) example

The following code opens directory /etc/passwd so that it can be read by readdir. For the callable service, see opendir (BPX1OPD, BPX4OPD) — Open a directory. AMODE 64 callers use BPX4OPD (opendir) example.

                                              
         MVC   BUFLENA,=F'11'                                           
         MVC   BUFFERA(11),=CL11'/etc/passwd'                           
         SPACE ,                                                        
         CALL  BPX1OPD,              Open a directory                  +
               (BUFLENA,             Input: Directory name length      +
               BUFFERA,              Input: Directory name             +
               RETVAL,               Return value:-1 or directory f.d. +
               RETCODE,              Return code                       +
               RSNCODE),             Reason code                       +
               VL,MF=(E,PLIST)       ---------------------------------- 
         ICM   R15,B'1111',RETVAL    Test RETVAL                        
         BL    PSEUDO                Branch if negative (-1 = failure)  
         ST    R15,DIRECTDES         Store the directory descriptor