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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How to stop MAC Address via IPTables

edit the /etc/sysconfig/iptables file and try to work whit this: -A INPUT -i (interface) -m mac (mac address) -j ACCEPT/DROP

tar+pbzip2 a dir

Check disk I/O

Get information about memory modules

To take information about the characteristics of the installed memory modules.

See entire packet payload using tcpdump.

This command will show you the entire payload of a packet. The final "s" increases the snaplength, grabbing the whole packet.

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 :-/

Remove comments and empty lines from a conf file

Some conf file are very long (squid.conf) This command help to read it.

multiline data block parse and CSV data extraction with perl

extract data in multiline blocks of data with perl pattern matching loop

Connect to FreeWifi hotspot (France) and keep the connection active

(In French) Connection aux hotspots FreeWifi, et maintien de la connection active

Type a random string into a X11 window

Just after you type enter, you have 3 seconds to switch window, then "texthere" will be "typed" in the X11 application that has focus. Very useful to beat your score at games such as "How fast can you type A-Z".

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Commands tagged perl (190)

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