Method do_capture

postscript.py:630–777

Capture further jobs to be printed on this device.

(self, arg)

    # ------------------------[ capture <operation> ]---------------------
    def do_capture(self, arg):
        "Capture further jobs to be printed on this device."
        free = '5'  # memory limit in megabytes that must at least be free to capture print jobs
        # record future print jobs
        if arg.startswith('start'):
            output().psonly()
            # PRET commands themself should not be capture if they're performed within ≤ 10s idle
            ''&#x27;
      ┌──────────┬───────────────────────────────┬───────────────┐
      │ hooking: │       BeginPage/EndPage       │ overwrite all │
      ├──────────┼───────────────────────────────┼───────────────┤
      │ metadat: │               ✔               │       -       │
      ├──────────┼───────────────────────────────┼───────┬───────┤
      │ globals: │   we are already global(?)    │ need  │ none  │
      ├──────────┼───────────────┬───────────────┼───────┴───────┤
      │ capture: │  currentfile  │   %lineedit   │  currentfile  │
      ├──────────┼───────┬───────┼───────┬───────┼───────┬───────┤
      │ storage: │ nfile │ vfile │ nfile │ array │ vfile │ nfile │
      ├──────────┼───────┼───────┼───────┼───────┼───────┼───────┤
      │ package: │   ✔   │   ?   │   ✔   │   ?   │   ?   │   ✔   │
      ├──────────┼───────┼───────┼───────┼───────┼───────┼───────┤
      │ execute: │   ✔   │   ✔   │   ✔   │   -   │   ✔   │   ✔   │
      └──────────┴───────┴───────┴───────┴───────┴───────┴───────┘
      ''&#x27;
            str_send = 'true 0 startjob {                                                     \n'\
                       '/setoldtime {/oldtime realtime def} def setoldtime                    \n'\
                       '/threshold {realtime oldtime sub abs 10000 lt} def                    \n'\
                       '/free {vmstatus exch pop exch pop 1048576 div '+free+' ge} def        \n'\
                       '%---------------------------------------------------------------------\n'\
                       '%--------------[ get current document as file object ]----------------\n'\
                       '%---------------------------------------------------------------------\n'\
                       '/document {(%stdin) (r) file /ReusableStreamDecode filter} bind def   \n'\
                       '%---------------------------------------------------------------------\n'\
                       '/capturehook {{                                                       \n'\
                       '  threshold {(Within threshold - will not capture\\n) print flush     \n'\
                       '  setoldtime                                                          \n'\
                       '}{                                                                    \n'\
                       '  setoldtime                                                          \n'\
                       '  free not {(Out of memory\\n) print flush}{                          \n'\
                       '  % (This job will be captured in memory\\n) print flush              \n'\
                       '  setoldtime                                                          \n'\
                       '  false echo                            % stop interpreter slowdown   \n'\
                       '  /timestamp realtime def               % get time from interpreter   \n'\
                       '  userdict /capturedict known not       % print jobs are saved here   \n'\
                       '  {/capturedict 50000 dict def} if      % define capture dictionary   \n'\
                       '  %-------------------------------------------------------------------\n'\
                       '  %--------------[ save document to dict and print it ]---------------\n'\
                       '  %-------------------------------------------------------------------\n'\
                       '  capturedict timestamp document put    % store document in memory    \n'\
                       '  capturedict timestamp get cvx exec    % print the actual document   \n'\
                       '  clear cleardictstack                  % restore original vm state   \n'\
                       '  %-------------------------------------------------------------------\n'\
                       '  setoldtime                                                          \n'\
                       '  } ifelse} ifelse} stopped} bind def                                 \n'\
                       '<< /BeginPage {capturehook} bind >> setpagedevice                     \n'\
                       '(Future print jobs will be captured in memory!)}                      \n'\
                       '{(Cannot capture - unlock me first)} ifelse print'
            output().raw(self.cmd(str_send))