You might consider system 'find'.

$ find /the/dir -name \*.dat -not -perm 644 -exec chmod 644 \{\} \;

[download]
find2perl can translate such a command to pure perl, but it doesn't understand +signed notation for the -perm any-bit argument (version dated 1998/04/07, easy to fix that).

Whatever solution you use, you can prune statting all regular files in a dir whose mtime is prior to the last run. chmod acts on the inode, not the file, so the directory times are what counts.

After Compline,
Zaxo

In reply to Re: Limitations to chmod and performance by Zaxo
in thread Limitations to chmod and performance by stefan k

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