in reply to Re: Linux Show Permissions: traverse file access
in thread Linux Show Permissions: traverse file access

Points for pointing out that `s/// for @array` is 50% faster than `grep {} @array`.

Points for telling me about `(?s:.*)` I did not know it could be written that way. It seems to be as fast as the other method (2% slightly faster), and might be more readable.

For the third one, it comes at the prices of understanding the intention of the line code. But if I just don't use newlines, it might be better. 

# perl -E '$x="abc\ndef"; $x=~s/.*/u/mi; say $x'
u
def
# perl -E '$x="abc\ndef"; $x=~s/[\s\S]*/u/mi; say $x'
u
# perl -E '$x="abc\ndef"; $x=~s/(?s:.*)/u/mi; say $x'
u

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Will test this one in the field for a while.

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Re^3: Linux Show Permissions: traverse file access
by jwkrahn (Abbot) on Oct 21, 2025 at 04:17 UTC
    Points for pointing out that `s/// for @array` is 50% faster than `grep {} @array`.

    You could also do all three s/// at the same time: 

        s/user::/USER:$o:/, s/group::/GROUP:$g:/, s/other::/OTHER::/ for @
+A;

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    For the third one, it comes at the prices of understanding the intention of the line code. But if I just don't use newlines, it might be better.

    Another way to do that which may be better: 

        $P{$k} =~ tr/ \n\r\t\f/ /s; # remove newlines

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    Naked blocks are fun! -- Randal L. Schwartz, Perl hacker
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