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mysticbbs 2012-03-08 13:29:42 -05:00
parent e987e9c9b2
commit 7073f62a78
1 changed files with 1 additions and 105 deletions

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@ -162,107 +162,3 @@ Begin
End; End;
End. End.
program procoutlarge;
{
Copyright (c) 2004-2011 by Marc Weustink and contributors
This example is created in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
}
// This is a
// WORKING
// demo program that shows
// how to launch an external program
// and read from its output.
uses
Classes, Process, SysUtils;
const
READ_BYTES = 2048;
var
OurCommand: String;
OutputLines: TStringList;
MemStream: TMemoryStream;
OurProcess: TProcess;
NumBytes: LongInt;
BytesRead: LongInt;
begin
// A temp Memorystream is used to buffer the output
MemStream := TMemoryStream.Create;
BytesRead := 0;
OurProcess := TProcess.Create(nil);
// Recursive dir is a good example.
OurCommand:='invalid command, please fix the IFDEFS.';
{$IFDEF Windows}
//Can't use dir directly, it's built in
//so we just use the shell:
OurCommand:='cmd.exe /c "dir /s d:\dev\code\mystic\"';
{$ENDIF Windows}
{$IFDEF Unix}
//Needs to be tested on Linux/Unix:
OurCommand := 'ls --recursive --all -l /';
{$ENDIF Unix}
writeln('-- Going to run: ' + OurCommand);
OurProcess.CommandLine := OurCommand;
// We cannot use poWaitOnExit here since we don't
// know the size of the output. On Linux the size of the
// output pipe is 2 kB; if the output data is more, we
// need to read the data. This isn't possible since we are
// waiting. So we get a deadlock here if we use poWaitOnExit.
OurProcess.Options := [poUsePipes];
WriteLn('-- External program run started');
OurProcess.Execute;
while OurProcess.Running do
begin
// make sure we have room
MemStream.SetSize(BytesRead + READ_BYTES);
// try reading it
NumBytes := OurProcess.Output.Read((MemStream.Memory + BytesRead)^, READ_BYTES);
if NumBytes > 0
then begin
Inc(BytesRead, NumBytes);
Write('.') //Output progress to screen.
end
else begin
// no data, wait 100 ms
Sleep(100);
end;
end;
// read last part
repeat
// make sure we have room
MemStream.SetSize(BytesRead + READ_BYTES);
// try reading it
NumBytes := OurProcess.Output.Read((MemStream.Memory + BytesRead)^, READ_BYTES);
if NumBytes > 0
then begin
Inc(BytesRead, NumBytes);
Write('.');
end;
until NumBytes <= 0;
if BytesRead > 0 then WriteLn;
MemStream.SetSize(BytesRead);
WriteLn('-- External program run complete');
OutputLines := TStringList.Create;
OutputLines.LoadFromStream(MemStream);
WriteLn('-- External program output line count = ', OutputLines.Count, ' --');
for NumBytes := 0 to OutputLines.Count - 1 do
begin
WriteLn(OutputLines[NumBytes]);
end;
WriteLn('-- Program end');
OutputLines.Free;
OurProcess.Free;
MemStream.Free;
end.