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On Sun, 2009-01-04 at 15:50 +0100, Martin Herrman wrote: |
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> Note: ; is sequential, not optimized for multiple cores (I wonder if && is) |
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> |
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&& is a logic operator and operates sequential too. && only executes the |
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command to the right of the operator if the command to the left returns |
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success (0) for the return code. |
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&& does not perform any job control. |
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I have never looked into multi threading a shell script, though I |
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suppose it could be possible but fairly complex. You could execute |
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multiple jobs in the background using '&' and capture each process id |
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into an array with the ${!} parameter, which "Expands to the process ID |
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of the most recently executed background (asynchronous) command". Once |
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you have launched the multiple jobs, you could enter a loop that sleeps |
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a few seconds and then checks the status of each process id in the |
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array, waiting for them to disappear. Once a process id disappears, you |
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could remove the id from the array, launch another background process |
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and add it's process id to the array. |
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It may be simpler to use something like Perl, Python, Ruby or Java to |
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handle threading, as those languages have threading APIs. |
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-- |
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Brett Johnson <brett@××××.com> |
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