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On Saturday 29 May 2010 14:59:16 Alan McKinnon wrote: |
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> On Saturday 29 May 2010 17:05:34 Daniel D Jones wrote: |
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... |
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> > -exec (which potentially has problems with race conditions - -execdir |
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> > should almost always be used instead) runs the command once for each file |
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> > found. xargs will call the command once for as many files as it can fit |
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> > on the command line. For some instances, like rm, that probably isn't |
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> > significant. But if you're calling a complex process with lots of files, |
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> > the overhead of starting the many extra processes may be significant. |
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> |
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> Perhaps you don't know Joerg yet. When dealing with the man, it's important |
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> to know where he's coming from - and that is not "how Linux does stuff" |
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> |
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> He invariably refers to POSIX when mentioning standards. He uses this |
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> standard to ensure that his code will work on any *nix platform. This puts |
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> him at odds with the Linux crowd sometimes - two very different |
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> viewpoints. |
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I wasn't coming from a Linux perspective. I'm a network engineer. At work, I |
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touch SSH servers running SunOS, file servers running BSD (don't recall what |
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flavor off the top of my head - I'm not in them that often), terminals running |
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HPUX and run Linux at home. xargs is available on all of them. |
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> It's not "-exec" that causes one processto be launched per item found, it |
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> is "-exec \;" |
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> |
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> He referred to "-exec +" which has the same behaviour as you mention - use |
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> as many filenames as will fit on the command line. |
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You're correct, of course. I missed that in the man pages. Mea culpa. (I'm |
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a network engineer, not a sysadmin.) |
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-- |
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"If "everybody knows" such-and-such, then it ain't so, by at least ten |
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thousand to one." - Robert A. Heinlein |
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