Use Unix truss command to monitor all operations and activity on a file

Hi Guys,
Can someone please give me an example of how to use the truss command to monitor all operations on a particular file.

I know there is an -r switch and reference to a file descriptor - but sure if this is simply a name of a file which you have to pass in or something different


Cheers



 B Cunney

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Barry CunneyAsked:
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chris_calabreseCommented:
A file descriptor is an integer that represents the file information in the kernel.

By convention, 0 is stdin, 1 is stdout, and 2 is stderr, so '-r 0' would mean monitoring reads to stdout.

If a program opens a fixed set of files, you can run truss against it to figure out what file descriptor ends up going to which file (by looking at the return value of the 'open' call).

If it opens different files based on user input, you'll proobably have to monitor all file descriptors since you won't know in advance which one goes with the file name you're interested in.
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Barry CunneyAuthor Commented:
Cheers chris,
I thought that there might be some trick one could use to get the truss command just to trace operations on one file
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chris_calabreseCommented:
You could probably write a perl script that monitors the output of truss and figures out which lines refer to a file of a particular name...
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