Commands tagged perl sorted by votes

Commands tagged perl (190)

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Realtime lines per second in a log file

Using tail to follow and standard perl to count and print the lps when lines are written to the logfile.
This is sample output - yours may be different.
5

tail -f /var/log/logfile|perl -e 'while (<>) {$l++;if (time > $e) {$e=time;print "$l\n";$l=0}}'

madsen · 2011-06-21 10:28:26 7
decoding Active Directory date format

When Ldapsearch queries an Active directory server, all the dates are shown using a timestamp of 18 digits. This perl regexp decodes them in a more human friendly notation. 11644473600 corresponds to some microsoft epoch. Show Sample Output
This is sample output - yours may be different.
```
badPasswordTime: DATE-AD(Mon Apr  6 20:53:42 2009)
lastLogon: DATE-AD(Mon Apr  6 20:55:07 2009)
pwdLastSet: DATE-AD(Tue Mar 24 12:53:42 2009)
accountExpires: DATE-AD(Sun Nov  1 00:00:00 2009)
```
4

ldapsearch -v -H ldap://<server> -x -D cn=<johndoe>,cn=<users>,dc=<ourdomain>,dc=<tld> -w<secret> -b ou=<lazystaff>,dc=<ourdomain>,dc=<tld> -s sub sAMAccountName=* '*' | perl -pne 's/(\d{11})\d{7}/"DATE-AD(".scalar(localtime($1-11644473600)).")"/e'

flux · 2009-04-22 00:57:34 5
uniq without pre-sorting

Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.
This is sample output - yours may be different.
4

perl -ne 'print if !$a{$_}++'

doherty · 2011-02-17 02:18:44 7
Find out if a module is installed in perl

Shows the path if the module is installed or exit quietly (to simply avoid the 'No documentation found' msg). Show Sample Output
This is sample output - yours may be different.
```
$ perldoc -l Net::Pcap 2>/dev/null
/usr/lib64/perl5/site_perl/5.12.3/x86_64-linux-thread-multi/Net/Pcap.pm
$ perldoc -l Figaro 2>/dev/null
$ echo $?
1
```
4

perldoc -l Module::Name 2>/dev/null

MarxBro · 2013-01-11 23:28:13 10
grep expression (perl regex) to extract all ip addresses from both ip and ifconfig commands output

It uses the following GNU grep options: "-o" which shows only the matching part of the line and "-P" which allows the use of Perl regular expressions. Show Sample Output
This is sample output - yours may be different.
```
[root@docker ~]# ip a | grep -oP '(?<=inet |addr:)(?:\d+\.){3}\d+'
127.0.0.1
10.0.2.15
172.17.0.1

[root@docker ~]# ifconfig  | grep -oP '(?<=inet |addr:)(?:\d+\.){3}\d+'
96.126.108.191
192.168.135.145
127.0.0.1
```
4

ip a | grep -oP '(?<=inet |addr:)(?:\d+\.){3}\d+'

acavagni · 2019-03-21 20:53:06 43
find the longest command in your history
This is sample output - yours may be different.
3

history | perl -lane '$lsize{$_} = scalar(@F); if($longest<$lsize{$_}) { $longest = $lsize{$_}; print "$_"; };' | tail -n1

salparadise · 2009-03-19 02:52:30 6
Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.

Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers. Show Sample Output
This is sample output - yours may be different.
```
echo "I had 10 goats, then sam brought 5 more. \
Then we bought 4 more goats and 2 goats had babies. \
How many goats did we have?" | \
perl -ne '$sum += $_ for grep { /\d+/ } split /[^\d\-\.]+/; print "$sum\n"'
21

perl -ne '$sum += $_ for grep { /\d+/ } split /[^\d\-\.]+/; print "$sum\n"'
1, '2' | 3, (-2) -.5
3.5
```
3

perl -ne '$sum += $_ for grep { /\d+/ } split /[^\d\-\.]+/; print "$sum\n"'

obscurite · 2009-06-16 06:39:08 6
Do a search-and-replace in a file after making a backup
This is sample output - yours may be different.
3

perl -i'.bak' -pe 's/old/new/g' <filename>

unixmonkey5248 · 2009-08-25 17:37:59 4
Find and display most recent files using find and perl

This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process. Show Sample Output
This is sample output - yours may be different.
```
find $HOME -type f -print0 | perl -0 -wn -e '@f=<>; foreach $file (@f){ (@el)=(stat($file)); push @el, $file; push @files,[ @el ];} @o=sort{$a->[9]<=>$b->[9]} @files; for $i (0..$#o){print scalar localtime($o[$i][9]), "\t$o[$i][-1]\n";}'|tail
Mon Sep 21 19:24:47 2009	/Users/andrew/Library/Logs/Sync/mobilemesyncstats.plist
Mon Sep 21 19:24:47 2009	/Users/andrew/Library/Preferences/ByHost/com.apple.DotMacSync.0019e366823e.plist
Mon Sep 21 19:24:48 2009	/Users/andrew/Library/Preferences/ByHost/com.apple.AOSNotification.0019e366823e.plist
Mon Sep 21 19:24:54 2009	/Users/andrew/Library/Cookies/Cookies.plist
Mon Sep 21 19:25:03 2009	/Users/andrew/Library/Preferences/com.apple.Terminal.plist
Mon Sep 21 19:26:44 2009	/Users/andrew/Library/Mail/IMAP-andrew@x-fifteen.com@mail.x-fifteen.com/Sent Messages.imapmbox/Messages/311191.emlx
Mon Sep 21 19:26:47 2009	/Users/andrew/Library/Logs/Sync/syncservices.log
Mon Sep 21 19:26:55 2009	/Users/andrew/Library/Preferences/com.apple.mail.plist
Mon Sep 21 19:27:48 2009	/Users/andrew/Library/Mail/IMAP-andrew@x-fifteen.com@mail.x-fifteen.com/INBOX.imapmbox/Messages/311201.emlx
Mon Sep 21 19:27:49 2009	/Users/andrew/Library/Mail/Envelope Index
```
3

find $HOME -type f -print0 | perl -0 -wn -e '@f=<>; foreach $file (@f){ (@el)=(stat($file)); push @el, $file; push @files,[ @el ];} @o=sort{$a->[9]<=>$b->[9]} @files; for $i (0..$#o){print scalar localtime($o[$i][9]), "\t$o[$i][-1]\n";}'|tail

drewk · 2009-09-21 22:11:16 11
Randomize lines (opposite of | sort)

random(6) - random lines from a file or random numbers
This is sample output - yours may be different.
3

random -f <file>

haplo · 2009-09-24 19:15:58 10
Convert files from DOS line endings to UNIX line endings

This method will also convert mac line endings.
This is sample output - yours may be different.
3

perl -pi -e 's/\r\n?/\n/g'

putnamhill · 2010-03-18 17:48:16 6
List all installed PERL modules by CPAN

This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc. Show Sample Output
This is sample output - yours may be different.
```
       Thu Jun 25 10:48:08 2009: "Module" IO::Dir::Recursive

       ?   "installed into: /usr/lib/perl5/site_perl/5.8.8"

       ?   "LINKTYPE: dynamic"

       ?   "VERSION: 0.03"

       ?   "EXE_FILES: "
```
3

perldoc perllocal

octopus · 2010-04-14 10:57:56 6

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 Show Sample Output

perl -pe 'eof()||s/\n/<SOMETEXT>/g' file.txt

eightmillion · 2010-12-02 01:19:27 5

read squid logs with human-readable timestamp

Show Sample Output
This is sample output - yours may be different.
```
before:
1310045550.240 0 10.10.10.27 TCP_HIT/200 1344 GET http://somedomain.com/ (...)
after:
[Thu Jul  7 15:32:30 2011].240 0 10.10.10.27 TCP_HIT/200 1344 GET http://somedomain.com (...)
```
3

tail -f /var/log/squid/access.log | perl -p -e 's/^([0-9]*)/"[".localtime($1)."]"/e'

godzillante · 2011-07-06 08:55:27 7
Use Perl like grep

If you've ever tried "grep -P" you know how terrible it is. Even the man page describes it as "highly experimental". This function will let you 'grep' pipes and files using Perl syntax for regular expressions. The first argument is the pattern, e.g. '/foo/'. The second argument is a filename (optional). Show Sample Output
This is sample output - yours may be different.
```
% printf "some\nfake\ntext\n" | prep '/^\s?[Ff]ake\s?$/'
fake
 
% printf "some\nfake\ntext\n" > file.txt

% prep '/^\s?[Ff]ake\s?$/' file.txt
fake
```
3

prep () { perl -nle 'print if '"$1"';' $2 }

dbbolton · 2011-08-13 14:29:26 6

interactive rss-based colorful commandline-fu reader perl oneliner (v0.1)

required packages: curl, xml2, html2text command is truncated, see 'sample output' Show Sample Output

open R,"curl -s http://feeds2.feedburner.com/Command-line-fu|xml2|"; while(<R>){ chomp; m(^/rss/channel/item/title=) and do{ s/^.*?=//; ($t,$d,$l)=($_,undef,undef) }; m(^/rss/channel/item/description=) and do{ s/^.*?=//; push @d,$_ }; m(^/rss/channel/item

bandie91 · 2012-02-24 23:40:02 5

Print environment information.

Print environment (system) information using Perl.
This is sample output - yours may be different.
3

perl -e 'print map { $_ .= "$ENV{$_}\n" } (keys %ENV)'

MarxBro · 2012-10-13 23:38:28 6
FizzBuzz in Perl

Just another FizzBuzz in Perl. Show Sample Output
This is sample output - yours may be different.
```
1
2
Fizz
4
Buzz
Fizz
7
8
Fizz
Buzz
11
Fizz
13
14
Fizzbuzz
```
3

perl -E 'say$_%15?$_%3?$_%5?$_:Buzz:Fizz:Fizzbuzz for 1..100'

MarxBro · 2012-11-18 05:47:29 32
Show all available colors on your terminal.

Using perl and tput, show all the colors with numbers that your actual $TERM can handle. If want to remove the numbers at beginning of new line, it should be something like this: perl -E 'say `tput setb $_`," "x `tput cols`, `tput sgr0` for 0 .. (`tput colors` - 1)'
This is sample output - yours may be different.
3

perl -E 'say $_,`tput setb $_`," "x(`tput cols`-length("$_")),`tput sgr0` for 0..(`tput colors`-1)'

MarxBro · 2012-11-22 01:55:51 6
Connect to all running screen instances

There was another line that was dependent on having un-named screen sessions. This just wouldn't do. This one works no matter what the name is. A possible improvement would be removing the perl dependence, but that doesn't effect me.
This is sample output - yours may be different.
2

for i in `screen -ls | perl -ne'if(/^\s+\d+\.([^\s]+)/){print $1, " "}'`; do gnome-terminal -e "screen -x $i"; done

hank · 2009-04-25 22:39:24 7
show the real times iso of epochs for a given column

When you have one of those (log)files that only has epoch for time (since no one will ever look at them as a date) this is a way to get the human readable date/time and do further inspection. Mostly perl-fu :-/
This is sample output - yours may be different.
2

perl -F' ' -MDate::Format -pale 'substr($_, index($_, $F[1]), length($F[1]), time2str("%C", $F[1]))' file.log

coffeeaddict_nl · 2009-08-13 13:57:33 4
Update twitter with Perl

Requires Net::Twitter. Just replace the double quoted strings with the appropriate info.
This is sample output - yours may be different.
2

perl -MNet::Twitter -e '$nt = Net::Twitter->new(traits => [qw/API::REST/], username => "YOUR USERNAME", password => "YOUR PASSWORD"); $ud = $nt->update("YOUR TWEET");'

dbbolton · 2010-06-16 19:46:05 4
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 Show Sample Output
This is sample output - yours may be different.
```
gjempty$ diff <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file1) <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file2)
247a248,250
> for ($i = 0; $i < 7; $i++) {
> if (!isset($tabData[$i])) $tabData[$i] = '';
> }

gjempty$ diff -b file1 file2
247a248,250
>                         for ($i = 0; $i < 7; $i++) {
>                             if (!isset($tabData[$i])) $tabData[$i] = '';
>                         }
```
2

diff <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file1) <(perl -wpl -e '$_ =~ s/^\s+|\s+$//g ;' file2)

jemptymethod · 2010-10-06 19:14:42 5
Find C/C++ source code comments

This is a naive way of finding source code comments in source code files that use C-like comments: // and /*...*/
This is sample output - yours may be different.
2

perl -e 'my $in_comment = 0; while (<>) { $in_comment = 1 if m{\Q/*\E}; print if $in_comment; $in_comment = 0 if m{\Q*/\E}; }' *.cpp

doherty · 2011-07-08 00:17:27 4
Randomize lines (opposite of | sort)

Randomizes a file. The opposite of sort is sort -R!
This is sample output - yours may be different.
2

sort -R

RyanM · 2011-07-15 15:35:27 3
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Decrypt exported android wallet keys for import into desktop client (LTC,FTC,BTC)

Shows how many percents of all avaliable packages are installed in your gentoo system

download the contents of a remote folder in the current local folder

Delicious search with human readable output

You can install filterous with $ sudo apt-get install libxslt1-dev; sudo easy_install -U filterous

Keep track of diff progress

You're running a program that reads LOTS of files and takes a long time. But it doesn't tell you about its progress. First, run a command in the background, e.g. $ find /usr/share/doc -type f -exec cat {} + > output_file.txt Then run the watch command. "watch -d" highlights the changes as they happen In bash: $! is the process id (pid) of the last command run in the background. You can change this to $(pidof my_command) to watch something in particular.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Simple Video Surveillance by email

This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail. Some systems support mail -a "References: " so that all video surveillance emails are grouped in a single email thread. To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!) For instance with Gmail, emails sent to me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com"

guitar synthesizer in one line of C

outputs a f=220Hz guitar string sound (fifth string A) needs ALSA

Write comments to your history.

A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Mount a Windows share on the local network (Ubuntu) with user rights and use a specific samba user

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Commands tagged perl (190)

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