* read stdin, write stdout and stderr
      * update exit status
      * define constants needed by programs that use this service pgm

      * define condition stdio_srvpgm when compiling the service pgm
      * but not when compiling programs that use the service pgm

     D TAB             c                   const(x'05')
     D CR              c                   const(x'0d')
     D LF              c                   const(x'25')
     D CRLF            c                   const(x'0d25')

     D stdin           pr            10i 0
     D   info                      4096a   varying

     D stdout          pr
     D   outfo                     4096    const varying

     D stderr          pr
     D   outfo                     4096    const varying

     D stdwrite        pr
     D   fd                          10i 0 value
     D   outfo                     4096    const varying

     D exit            pr
     D                                3u 0 value

      /if defined(stdio_srvpgm)

     D fread           pr            10i 0 extproc('read')
     D   fd                          10i 0 value
     D   info                          *   value
     D   length                      10u 0 value

     D fwrite          pr            10i 0 extproc('write')
     D   fd                          10i 0 value
     D   outfo                         *   value
     D   length                      10u 0 value

     D cexit           pr                  extproc('exit')
     D                                3u 0 value

      /endif