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Commands tagged perl from sorted by
Terminal - Commands tagged perl - 163 results
egrep -i "^[0-9a-f]{4,} .*$*" $(locate CharName.pm) | while read h d; do /usr/bin/printf "\U$(printf "%08x" 0x$h)\tU+%s\t%s\n" $h "$d"; done
2010-12-31 16:47:59
User: hackerb9
Functions: egrep locate read
Tags: bash perl grep unicode code points GNU coreutils
12
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Look up a unicode character by name

[Update! Thanks to a tip from ioggstream, I've fixed both of the bugs mentioned below.]

You, yes, 𝙔𝙊𝙐, can be the terror of the Internet! Why use normal, boring bullet points in your text, when you could use a ROTATED HEAVY BLACK HEART BULLET (❥)!? (Which would also be an awesome band name, by the way).



This script makes it easy to find unusual characters from the command line. You can then cut and paste them or, if you're using a GTK application, type Control+Shift+U followed by the code point number (e.g., 2765) and then a SPACE.



USAGE: Put this script in a file (I called mine "ugrep") and make it executable. Run it from the command line like so,



ugrep heart



The output will look like this,



☙ U+2619 REVERSED ROTATED FLORAL HEART BULLET

♡ U+2661 WHITE HEART SUIT

♥ U+2665 BLACK HEART SUIT

❣ U+2763 HEAVY HEART EXCLAMATION MARK ORNAMENT

❤ U+2764 HEAVY BLACK HEART

❥ U+2765 ROTATED HEAVY BLACK HEART BULLET

❦ U+2766 FLORAL HEART

❧ U+2767 ROTATED FLORAL HEART BULLET

⺖ U+2E96 CJK RADICAL HEART ONE

⺗ U+2E97 CJK RADICAL HEART TWO

⼼ U+2F3C KANGXI RADICAL HEART



You can, of course, use regular expressions. For example, if you are looking for the "pi" symbol, you could do this:



ugrep '\bpi\b'



REQUIREMENTS: Although this is written in Bash, it assumes you have Perl installed because it greps through the Perl Unicode character name module (/usr/lib/perl5/Unicode/CharName.pm). Note that it would not have made more sense to write this in Perl, since the CharName.pm module doesn't actually include a subroutine for looking up a character based on the description. (Weird.)



BUGS: In order to fit this script in the commandlinefu limits, a couple bugs were added. ① Astral characters beyond the BMP (basic multilingual plane) are not displayed correctly, but see below. ② Perl code from the perl module being grepped is sometimes extraneously matched.



MISFEATURES: Bash's printf cannot, given a Unicode codepoint, print the resulting character to the terminal. GNU's coreutils printf (usually "/usr/bin/printf") can do so, but it is brokenly pedantic about how many hexadecimal digits follow the escape sequence and will actually die with an error if you give the wrong number. This is especially annoying since Unicode code points are usually variable length with implied leading zeros. The CharNames.pm file represents BMP characters as 4 hexits, but astral characters as 5. In the actual version of this script that I use, I've kludged around this misfeature by zero-padding to 8 hexits like so,



/usr/bin/printf "\U$(printf "%08x" 0x$hex)"



TIP 1: The author recommends "xsel" for command line cut-and-paste. For example,



ugrep biohazard | xsel



TIP 2: In Emacs, instead of running this command in a subshell, you can type Unicode code points directly by pressing Control-Q first, but you'll likely want to change the default input from octal to hexadecimal. (setq read-quoted-char-radix 16).



TIP 3: Of course, if you're using X, and you want to type one of the more common unusual characters, it's easiest of all to do it with your Compose (aka Multi) key. For example, hitting [Compose] <3 types ♥.

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cat /dev/urandom | hexdump -C | highlight ca fe 3d 42 e1 b3 ae f8 | perl -MTime::HiRes -pne "Time::HiRes::usleep(rand()*1000000)"
2010-12-29 21:26:18
User: doherty
Functions: cat hexdump perl
Tags: bash perl hexdump random highlight
1
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shell equivalent of a boss button

Nobody wants the boss to notice when you're slacking off. This will fill your shell with random data, parts of it highlighted. Note that 'highlight' is the Perl module App::highlight, not "a universal sourcecode to formatted text converter." You'll also need Term::ANSIColor.

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pcregrep -r --exclude_dir='.svn' --include='.*jsp$' -A 2 -B 2 --color "pHtmlHome" .
2010-12-09 15:26:07
User: hute37
Tags: perl grep
0
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Recursive source regexp search with pcregrep

range context (-A -B) search, with exclusion of vcs directories

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perl -e 'for(;;){@d=split("",`date +%H%M%S`);print"\r";for(0..5){printf"%.4b ",$d[$_]}sleep 1}'
2010-12-04 00:05:54
User: putnamhill
Functions: perl
Tags: perl binary clock
9
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Binary clock

Fun idea! This one adds seconds and keeps running on the same line. Perl's probably cheating though. :)

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perl -pe 'eof()||s/\n/<SOMETEXT>/g' file.txt
2010-12-02 01:19:27
User: eightmillion
Functions: perl
Tags: Text Processing perl
3
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Join lines

This command turns a multi-line file into a single line joined with <SOMETEXT>. To skip blank lines, use:

perl -pe '(eof()||s/^\s*$//)||s/\n/<SOMETEXT>/g' file.txt
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find . -type f -print0 | xargs -0 perl -pi.save -e 'tr/A-Z/a-z/'
2010-11-25 13:55:34
User: depesz
Functions: find perl xargs
Tags: perl find regex
1
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recursive transform all contents of files to lowercase

In this way it doesn't have problems with filenames with spaces.

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perl -e "tr/[A-Z]/[a-z]/;" -pi.save $(find . -type f)
2010-11-25 12:48:39
User: miccaman
Functions: find perl
Tags: perl find regex
0
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recursive transform all contents of files to lowercase
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pcharc(){ perl -e 'for (0..255) {$_ = chr($_); print if /['$1']/}' | cat -v; echo;}
2010-11-13 00:32:41
User: putnamhill
Functions: cat perl
Tags: perl
1
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print character classes

Today I needed a way to print various character classes to use as input for a program I was writing. Also a nice way to visualize character classes.

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pcregrep --color -M -N CRLF "owa_pattern\.\w+\W*\([^\)]*\)" source.sql
2010-11-11 12:53:40
User: hute37
Tags: perl grep regex
0
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Source multiline grep with pcregrep

grep multiline in Perl regexp syntax with pcregrep

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git status | perl -F'\s' -nale 'BEGIN { $a = 0 }; $a = 1 if $_ =~ /changed but not updated/i; print $F[-1] if ( $a && -f $F[-1] )'
2010-10-15 07:58:14
User: coffeeaddict_nl
Functions: perl
Tags: status git perl
0
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Show the changed files in your GIT repo

Parse the output of git status.

Once the line '# Changed but not updated:' has passed print every last part of the line if it exists on disk.

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diff <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file1) <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file2)
2010-10-06 19:14:42
User: jemptymethod
Functions: diff perl
Tags: bash diff perl
2
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diff files while disregarding indentation and trailing white space

**NOTE** Tekhne's alternative is much more succinct and its output conforms to the files actual contents rather than with white space removed

My command on the other hand uses bash process substitution (and "Minimal" Perl), instead of files, to first remove leading and trailing white space from lines, before diff'ing the streams. Very useful when differences in indentation, such as in programming source code files, may be irrelevant

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find . -iname '*.jpg' -type f -print0 |perl -0 -ne '$a+=-s $_;END{print "$a\n"}'
2010-09-12 13:14:12
User: unixmonkey10455
Functions: find perl
Tags: size perl find du filesize
1
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Summarize size of all files of given type in all subdirectories (in bytes)

This deals nicely with filenames containing special characters and can deal with more files than can fit on a commandline. It also avoids spawning du.

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perl -le 'chomp($w=`which $ARGV[0]`);$_=`file $w`;while(/link\b/){chomp($_=(split/`/,$_)[1]);chop$_;$w.=" -> $_";$_=`file $_`;}print "\n$w";' COMMAND_NAME
2010-07-30 19:26:35
User: dbbolton
Functions: perl
Tags: which perl binary file PATH command
0
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Show full path followed by a command

This will show you any links that a command follows (unlike 'file -L'), as well as the ultimate binary or script.

Put the name of the command at the very end; this will be passed to perl as the first argument.

For obvious reasons, this doesn't work with aliases or functions.

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echo "text" | hd
2010-07-20 15:40:52
User: Vilemirth
Functions: echo
Tags: perl hex ascii
1
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Convert ascii string to hex
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echo "text" | od -t x1
2010-07-14 14:53:25
User: max_allan
Functions: echo od
Tags: perl hex ascii
0
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Convert ascii string to hex

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.

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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
1
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Convert ascii string to hex

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"}'
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perl -e 'print "\x41\x72\x74\x20\x6f\x66\x20\x68\x61\x63\x6b\x69\x6e\x67\x2e\x2e\x2e\n" x 100'
2010-07-11 16:32:00
User: gunslinger_
Functions: perl
Tags: perl shellcode
-15
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Art of hacking on perl

Print "Art of hacking..." 100 times by perl

or you can this tools : http://packetstormsecurity.org/shellcode/shellcodeencdec.py.txt

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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
-3
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Replace tabs with spaces in file

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

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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
Tags: net twitter perl update tweet
2
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Update twitter with Perl

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

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git log -p -z | perl -ln0e 'print if /[+-].*searchedstring/'
2010-06-13 07:41:22
User: takeshin
Functions: perl
Tags: git perl log search
1
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See all the commits for which searchstring appear in the git diff
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aptitude purge linux-image | grep ^i | grep -v $(uname -r)
2010-06-11 22:20:42
User: lgallardo
Functions: grep uname
Tags: Debian Linux perl kernel aptitude
-4
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Remove all unused kernels with apt-get
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perl -e 'chomp($k=`uname -r`); for (</boot/vm*>) {s/^.*vmlinuz-($k)?//; $l.="linux-image-$_ ";} system "aptitude remove $l";'
2010-06-10 22:16:47
User: dbbolton
Functions: perl
Tags: Debian Linux perl kernel aptitude
1
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Remove all unused kernels with apt-get

TIMTOWTDI

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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
Tags: perl directory syntax
0
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Check syntax of all Perl modules or scripts underneath the current directory

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

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perl -e 'foreach (@ARGV) {@T=stat($_); print localtime($T[8])." - ".$_."\n"}'
2010-05-20 16:19:17
User: putnamhill
Functions: perl
Tags: perl solaris ls file time
0
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Print time and year of file in Solaris (or other Unix ls command that does not have a simple
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perl -e '@F = `ls -1`;while (<@F>){@T = stat($_);print "$_ = " . localtime($T[8]) . "\n";}'
2010-05-20 15:02:51
User: hckhckhck
Functions: perl
Tags: perl solaris ls file time
0
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Print time and year of file in Solaris (or other Unix ls command that does not have a simple "--full-list")

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.

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