01-16-2009
command line explanation
Hello everyone,
I found this command line in a website:
perl -pi.bak -we's/\z/Your new line\n/ if $. == 2;' your_text_file.txt
With this command line you can insert a new line anywhere you want in a text without overwriting what's in it.
-p causes perl to assume a loop around your file so that you can process it.
i.bak creates a back up file
-w turns on warnings.
-e is the script you want to execute.
Does anyone know what s/\z/ is for?
Thanks a lot.
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LEARN ABOUT DEBIAN
prename
RENAME(1) Perl Programmers Reference Guide RENAME(1)
NAME
rename - renames multiple files
SYNOPSIS
rename [ -v ] [ -n ] [ -f ] perlexpr [ files ]
DESCRIPTION
"rename" renames the filenames supplied according to the rule specified as the first argument. The perlexpr argument is a Perl expression
which is expected to modify the $_ string in Perl for at least some of the filenames specified. If a given filename is not modified by the
expression, it will not be renamed. If no filenames are given on the command line, filenames will be read via standard input.
For example, to rename all files matching "*.bak" to strip the extension, you might say
rename 's/.bak$//' *.bak
To translate uppercase names to lower, you'd use
rename 'y/A-Z/a-z/' *
OPTIONS
-v, --verbose
Verbose: print names of files successfully renamed.
-n, --no-act
No Action: show what files would have been renamed.
-f, --force
Force: overwrite existing files.
ENVIRONMENT
No environment variables are used.
AUTHOR
Larry Wall
SEE ALSO
mv(1), perl(1)
DIAGNOSTICS
If you give an invalid Perl expression you'll get a syntax error.
BUGS
The original "rename" did not check for the existence of target filenames, so had to be used with care. I hope I've fixed that (Robin
Barker).
perl v5.14.2 2014-09-26 RENAME(1)