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Commands tagged perl from sorted by
Terminal - Commands tagged perl - 175 results
echo "text" | hd
echo "text" | od -t x1
2010-07-14 14:53:25
User: max_allan
Functions: echo od
Tags: perl hex ascii

Just use "od" and it can also dump in decimal or octal.

(use -t x1 and not just -x or it confuses the byte order)

There is a load of other formatting options, I'm not sure if you can turn off the address at the start of the line.

echo -n 'text' | perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg'
2010-07-14 12:20:42
User: putnamhill
Functions: echo perl
Tags: perl hex ascii

Here's a version that uses perl. If you'd like a trailing newline:

perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg; END {print "\n"}'
perl -e 'print "\x41\x72\x74\x20\x6f\x66\x20\x68\x61\x63\x6b\x69\x6e\x67\x2e\x2e\x2e\n" x 100'
cat file_with_tabs.txt | perl -pe 's/\t/ /g'
2010-07-11 13:01:22
User: nikc
Functions: cat perl
Tags: cat perl replace

Replaces tabs in output with spaces. Uses perl since sed seems to work differently across platforms.

perl -MNet::Twitter -e '$nt = Net::Twitter->new(traits => [qw/API::REST/], username => "YOUR USERNAME", password => "YOUR PASSWORD"); $ud = $nt->update("YOUR TWEET");'
2010-06-16 19:46:05
User: dbbolton
Functions: perl

Requires Net::Twitter. Just replace the double quoted strings with the appropriate info.

git log -p -z | perl -ln0e 'print if /[+-].*searchedstring/'
aptitude purge linux-image | grep ^i | grep -v $(uname -r)
perl -e 'chomp($k=`uname -r`); for (</boot/vm*>) {s/^.*vmlinuz-($k)?//; $l.="linux-image-$_ ";} system "aptitude remove $l";'
for code in $(find . -type f -name '*.p[ml]'); do perl -c "$code"; done
2010-05-29 23:26:40
User: udog
Functions: find perl

Finds all *.p[ml]-files and runs a perl -c on them, checking whether Perl thinks they are syntactically correct

perl -e 'foreach (@ARGV) {@T=stat($_); print localtime($T[8])." - ".$_."\n"}'
perl -e '@F = `ls -1`;while (<@F>){@T = stat($_);print "$_ = " . localtime($T[8]) . "\n";}'
2010-05-20 15:02:51
User: hckhckhck
Functions: perl

Solaris 'ls' command does not have a nice '--full-time' arg to make the time show after a year has passed. So I spit this out quick. It hates spaces in file names.

perl -MDigest::SHA -e 'print substr( Digest::SHA::sha256_base64( time() ), 0, $ARGV[0] ) . "\n"' <length>
2010-04-30 21:45:46
User: udog
Functions: perl

Of course you will have to install Digest::SHA and perl before this will work :)

Maximum length is 43 for SHA256. If you need more, use SHA512 or the hexadecimal form: sha256_hex()

echo $hex | perl -pe 's/(..)/chr(hex($1))/ge'
perl -i -pe 's/\r/\n/g' file
perldoc perllocal
2010-04-14 10:57:56
User: octopus
Tags: version perl

This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc.

curl -s http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}|xmlstarlet sel -E utf-8 -t -m //forecast/txt_forecast/forecastday -v fcttext -n
perl -MStatistics::Descriptive -alne 'my $stat = Statistics::Descriptive::Full->new; $stat->add_data(@F[1..4]); print $stat->variance' filename
2010-04-02 21:16:12
User: alperyilmaz
Functions: perl

In this example, file contains five columns where first column is text. Variance is calculated for columns 2 - 5 by using perl module Statistics::Descriptive. There are many more statistical functions available in the module.

perl -pi -e 's/\r\n?/\n/g'
2010-03-18 17:48:16
User: putnamhill
Functions: perl
Tags: perl

This method will also convert mac line endings.

perl -ne 'BEGIN{undef $/}; print "$ARGV\t$.\t$1\n" if m/(first line.*\n.*second line)/mg'
2010-03-18 15:46:10
User: hfs
Functions: perl
Tags: perl grep

Using perl you can search for patterns spanning several lines, a thing that grep can't do. Append the list of files to above command or pipe a file through it, just as with regular grep. If you add the 's' modifier to the regex, the dot '.' also matches line endings, useful if you don't known how many lines you need are between parts of your pattern. Change '*' to '*?' to make it greedy, that is match only as few characters as possible.

See also http://www.commandlinefu.com/commands/view/1764/display-a-block-of-text-with-awk to do a similar thing with awk.

Edit: The undef has to be put in a begin-block, or a match in the first line would not be found.

echo "$url" | perl -MURI::Escape -ne 'chomp;print uri_escape($_),"\n"'
2010-02-13 00:44:48
User: eightmillion
Functions: echo perl
Tags: perl

Converts reserved characters in a URI to their percent encoded counterparts.

Alternate python version:

echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'
weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "%s: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';}
2010-02-10 01:23:39
User: eightmillion
Functions: perl

This shell function grabs the weather forecast for the next 24 to 48 hours from weatherunderground.com. Replace <YOURZIPORLOCATION> with your zip code or your "city, state" or "city, country", then calling the function without any arguments returns the weather for that location. Calling the function with a zip code or place name as an argument returns the weather for that location instead of your default.

To add a bit of color formatting to the output, use the following instead:

weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "\x1B[0;34m%s\x1B[0m: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';}

Requires: perl, curl

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Eo '<li>[^<]+'|sed 's/^<li>//g'|nl|/usr/bin/perl -MHTML::Entities -pe 'decode_entities($_)';}
2010-01-30 13:08:03
User: gthb
Functions: grep sed

This version works on Mac (avoids grep -P, adding a sed step instead, and invokes /usr/bin/perl with full path in case you have another one installed).

Still requires that you install perl module HTML::Entities ? here's how: http://www.perlmonks.org/?node_id=640489

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?<=<li>)[^<]+'|nl|perl -MHTML::Entities -pe 'decode_entities($_)' 2>/dev/null;}
2010-01-29 05:01:11
User: eightmillion
Functions: grep perl

This function takes a word or a phrase as arguments and then fetches definitions using Google's "define" syntax. The "nl" and perl portion isn't strictly necessary. It just makes the output a bit more readable, but this also works:

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?<=<li>)[^<]+';}

If your version of grep doesn't have perl compatible regex support, then you can use this version:

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Eo '<li>[^<]+'|sed 's/<li>//g'|nl|perl -MHTML::Entities -pe 'decode_entities($_)' 2>/dev/null;}
podwebserver& sleep 2; elinks ''
2010-01-27 10:57:34
User: vlan7
Functions: sleep

Prerequisites: module Pod::Webserver installed. You can install it typing:

sudo perl -MCPAN -e 'install Pod::Webserver'

You can replace elinks with your fav browser. For FF:

podwebserver& sleep 2; firefox -remote 'openurl(, new-tab )'

If you have Firefox open, this will pop-up the index web in a new tab.