BPX1POL (poll) example

The following code issues a poll. For the callable service, see poll (BPX1POL, BPX4POL) — Monitor activity on file descriptors and message queues. For the data structure, see BPXYPOLL — Map poll syscall parameters. AMODE 64 callers use BPX4POL (poll) example.

                                              
         LA    R15,BUFFERA                                              
         USING POLLFD,R15                                               
         ST    R15,BUFA              ->BPXYPOLL structure               
*        MVC   POLLHFD(4),file_descriptor_number2                       
         MVI   POLLEVENTS,0                                             
         MVI   POLLEVENTS+1,POLLERDNORM                                 
         A     R15,=A(POLLFD#LENGTH)                                    
*        MVC   POLLHFD(4),file_descriptor_number1                       
         MVI   POLLEVENTS,0                                             
         MVI   POLLEVENTS+1,POLLEWRNORM                                 
         SPACE ,                                                        
         CALL  BPX1POL,              Create a pipe                     +
               (BUFA,                Input: address of BPXYPOLL        +
               =A(2),                Input: number of BPXYPOLL structs +
               =A(0),                Input: -1, 0, milliseconds        +
               RETVAL,               Return value: 0 or -1             +
               RETCODE,              Return code                       +
               RSNCODE),             Reason code                       +
               VL,MF=(E,PLIST)       ----------------------------------