You really should have tested it:

This (tested!) script would work as:

perl -i.bak -n -e"print if(m/foo/);" foo.txt bar.txt baz.txt

From perldoc perlrun:

-n causes Perl to assume the following loop around your program, which makes it iterate over filename arguments somewhat like sed -n or awk: LINE: while (<>) { ... # your program goes here } "BEGIN" and "END" blocks may be used to capture control before or after the implicit program loop, just as in awk. -p causes Perl to assume the following loop around your program, which makes it iterate over filename arguments somewhat like sed: LINE: while (<>) { ... # your program goes here } continue { print or die "-p destination: $!\n"; } If a file named by an argument cannot be opened for some reason, Perl warns you about it, and moves on to the next file. Note that the lines are printed automatically. An error occurring during printing is treated as fatal. To suppress printing use the -n switch. A -p overrides a -n switch. "BEGIN" and "END" blocks may be used to capture control before or after the implicit loop, just as in awk.

In reply to Re: Re: Re: Large file processed line by line by mirod
in thread Large file processed line by line by sdyates2001

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