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i=1; for f (*.jpg) zmv $f '${(l:3::0:)$((++i))}'$f
2013-03-21 01:51:28
User: khayyam
Tags: zsh
0
Up
Down
Batch rename and number files

zsh example using a 'for' loop and arithmetic expression:

files matching the pattern '*.jpg' are renamed with a 3 digit prefix, keeping the previous filename and suffix.

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lsof -ni TCP
2013-03-20 22:51:16
User: tsener
Tags: lsof
1
Up
Down
Open Port Check

also could specify port number:

lsof -ni TCP:80

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ack --type=php <string>
2013-03-20 20:27:31
User: khayyam
Tags: ack
0
Up
Down
find str in in a directory which file extension is .php

The 'sample output' shows the file(s) found and the line at which '' was found (for the example I used the 'string'.)

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find -type f | xargs ls -1tr
2013-03-20 16:43:54
User: unixmonkey50727
Functions: find ls xargs
Tags: find ls xargs
0
Up
Down
Find files and list them sorted by modification time
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nc -l <port-number>
2013-03-20 15:25:57
User: cybertoast
Tags: networking firewall socket port listen
-1
Up
Down
Listen on an arbitrary port

Simple way to test if a port is available to the public. Run this command on the "server" and run a `telnet host-ip port-number` on the client. Test by sending strings to the server, which will be displayed in the server terminal.

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rpm -qa --queryformat '%{size} %{name}-%{version}-%{release}\n' | sort -k 1,1 -rn | nl | head -16
2013-03-19 21:10:54
User: mpb
Functions: head nl rpm sort
0
Up
Down
Display 16 largest installed RPMs in size order, largest first

Interesting to see which packages are larger than the kernel package.

Useful to understand which RPMs might be candidates to remove if drive space is restricted.

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count=0;while IFS= read -r -d '' line; do echo "${line#* }"; ((++count==5)) && break; done < <(find . -type f -printf '%s %p\0' | sort -znr)
2013-03-19 17:19:26
User: sharfah
Functions: echo find read sort
Tags: sort find head,
-4
Up
Down
Find top 5 big files

This command is more robust because it handles spaces, newlines and control characters in filenames. It uses printf, not ls, to determine file size.

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alias clearscrollback='clear;printf %b "\033[3J"'
2013-03-19 14:18:22
User: richardellisjr
Functions: alias printf
0
Up
Down
Create an alias command that clears the screen and scroll back buffer (in putty and xterm)
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for FILE in *.conf; do cp $FILE{,.`date +%Y%m%dt%M:%H:%S`}; done
2013-03-19 14:13:04
User: richardellisjr
Functions: cp
0
Up
Down
Backup all files matching a pattern to files with a timestamp
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hello, too
2013-03-19 13:41:10
User: Lisa2
0
Up
Down
hello

my name's lisa

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alias cls='clear;ls'
2013-03-19 12:18:47
User: opexxx
Functions: alias
Tags: ls clear
0
Up
Down
Clear the screen and list file

Clear the screen and list file

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find . -type f -exec ls -s {} \; | sort -n -r | head -5
2013-03-19 12:16:24
User: opexxx
Functions: find head ls sort
Tags: sort find head,
-3
Up
Down
Find top 5 big files

Find top 5 big files

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'
2013-03-19 11:45:47
User: opexxx
Functions: alias
0
Up
Down
Add an "alert" alias for long running commands

Add an "alert" alias for long running commands

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lsof -i -P +c 0 +M | grep -i "$1"
2013-03-19 10:42:15
User: opexxx
Functions: grep
Tags: grep lsof
0
Up
Down
identify active network connections
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netstat -an | grep --color -i -E 'listen|listening'
2013-03-19 08:53:47
User: opexxx
Functions: grep netstat
Tags: grep netstat
-1
Up
Down
Open Port Check

Open Port Check

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tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'
2013-03-18 18:55:20
User: ene2002
Functions: grep strings tcpdump
1
Up
Down
SMTP Analysis

This works just as well for SMTP. You could run this on your mail server to watch e-mail senders and recipients:

tcpdump -l -s0 -w - tcp dst port 25 | strings | grep -i 'MAIL FROM\|RCPT TO'

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nmap --script=http-waf-fingerprint --script-args http-waf-fingerprint.intensive=1 192.168.56.254
2013-03-18 18:50:22
User: ene2002
-2
Up
Down
NMAP
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sed "s,\x1B\[[0-9;]*[a-zA-Z],,g"
2013-03-18 14:49:30
User: Zhoul
Functions: sed
0
Up
Down
Remove ( color / special / escape / ANSI ) codes, from text, with sed

Remove ( color / special / escape / ANSI ) codes, from text, with sed

Credit to the original folks who I've copied this command from.

The diff here is:

Theirs: [m|K]

Theirs is supposed to remove \E[NUMBERS;NUMBERS[m OR K]

This statement is incorrect in 2 ways.

1. The letters m and K are two of more than 20+ possible letters that can end these sequences.

2. Inside []'s , OR is already assumed, so they are also looking for sequences ending with | which is not correct.

This : [a-zA-Z]

This resolves the "OR" issue noted above, and takes care of all sequences, as they all end with a lower or upper cased letter.

This ensures 100% of any escape code 'mess' is removed.

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find /some/path -type f -printf '%f\n' | grep -o '\..\+$' | sort | uniq -c | sort -rn
2013-03-18 14:42:29
User: skkzsh
Functions: find grep sort uniq
Tags: sort uniq find grep extension
2
Up
Down
list unique file extensions recursively for a path, include extension frequency stats

Get the longest match of file extension (Ex. For 'foo.tar.gz', you get '.tar.gz' instead of '.gz')

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find /some/path -type f | gawk -F/ '{print $NF}' | gawk -F. '/\./{print $NF}' | sort | uniq -c | sort -rn
2013-03-18 14:40:26
User: skkzsh
Functions: find gawk sort uniq
Tags: sort awk uniq find extension
0
Up
Down
list unique file extensions recursively for a path, include extension frequency stats

If you have GNU findutils, you can get only the file name with

find /some/path -type f -printf '%f\n'

instead of

find /some/path -type f | gawk -F/ '{print $NF}'
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md5sum filename | ncat hash.cymru.com 43
2013-03-18 14:24:12
User: opexxx
Functions: md5sum
Tags: md5sum ncat
2
Up
Down
cymru malware check
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sed '/^$/d'
2013-03-18 14:16:42
User: opexxx
Functions: sed
2
Up
Down
Remove blank lines
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cat -s
2013-03-18 14:15:48
User: opexxx
Functions: cat
6
Up
Down
Compress blank lines
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sed "s/\b\(.\)/\u\1/g"
2013-03-18 14:15:13
User: opexxx
Functions: sed
1
Up
Down
Capitalize the first letter of every word
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grep -E '([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})\.([0-9]{1,3})' -o tmp
2013-03-18 14:12:22
User: opexxx
Functions: grep
0
Up
Down
Extract all IPs from a file
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate