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| − | | + | ===Reading large output=== |
| − | == Improved example didn't work for me == | + | NB: use AProcess.Output.Read(Buffer'''[0]''', BUF_SIZE) for dynamic Buffer |
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| − | I copied the improved example and tried to compile it in lazarus 0.9.7 beta (Date: 22-05-05), using fpc version 2.0.0 [2005/05/16] for i386 - linux, and it gave me this error:
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| − | project1.lpr(44,15) Error: identifier idents no member "Lines"
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| − | project1.lpr(44,35) Error: Illegal expression
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| − | project1.lpr(44,35) Fatal: Syntax error, ";" expected but "(" found
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| − | The line with error is:
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| − | AStringList.Lines.ReadFromStream(AProcess.Output);
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| − | What's wrong ?
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| − | : I fixed the example. [[User:Vincent|Vincent]] 04:57, 23 May 2005 (PDT)
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| − | It compiles now, but when I run it freezes. Running step by step I found that it freezes at the line:
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| − | AProcess.Execute;
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| − | From a console window, I saw the ppc386 process still running. Then I run 'killall ppc38' and the lazarus program unfroze, and the output.txt file had the right content.
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| − | I searched the web a little, and found and alternative way to set WaitOnExit, by changing it this way:
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| − | // AProcess.Options := AProcess.Options + [poWaitOnExit, poUsePipes];
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| − | AProcess.WaitOnExit;
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| − | Now, when I run it raises an error window with the saying:
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| − | Project projet1 raised exception class 'External: SIGSEGV'
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| − | ----
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| − | :: If you don't give the option ''poUsePipes'', there are no streams to read from. [[User:Vincent|Vincent]] 02:16, 25 May 2005 (PDT)
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| − | When I click "OK", this windows opens:
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| − | Execution Paused
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| − | Adress: $08064782
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| − | Procedure: CLASSES_TSTRINGS_$__LOADFROMSTREAM$TSTREAM
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| − | File:
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| − | (Some day an assembler window might popup here:)
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| − | I click "OK" again and it shows that the execution stopped at the line:
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| − | AStringList.LoadFromStream(AProcess.Output);
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| − | Running step by step I confirm that it's this line that raised this excecption.
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| − | What can I do ?
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| − | : I added an example to read more output from the pipe. Tests on my computer indicated a buffer of 64 KB, so unless the output was more then 64 KB, I did not run into trouble. Maybe the pipe buffer on your computer is smaller, so the deadlock occurs for smaller output too.
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