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I have this as a file called deletekey in my ~/bin.
Makes life a little easier.
In this case it's better do to use the dedicated tool
Prints the 4th line and then quits. (Credit goes to flatcap in comments: http://www.commandlinefu.com/commands/view/6031/print-just-line-4-from-a-textfile#comment.)
I wrote this script to speed up Nginx configs. This (long) one liner can be run via BASH. You will see that we set a variable in bash called 'foo' and the streamline editor (sed) finds 'bar' in 'foo.conf' next it writes that output to a temp file (foo.temp) and removes the first 5 lines (that aren't needed in this case) & lastly it moves (overwrites) foo.temp to foo.conf
Most systems (at least my macbook) have system users defined, such as _www and using "users" for example will not list them. This command allows you to see who the 'virtual' users are on your system.
The above output is for a custom compiled version of Vim on Arch Linux.
Just a quick shell one liner, and presents a list of all the enabled and disabled (those prefixed with a '-') features.
This shows every bit of information that stat can get for any file, dir, fifo, etc. It's great because it also shows the format and explains it for each format option.
If you just want stat help, create this handy alias 'stath' to display all format options with explanations.
alias stath="stat --h|sed '/Th/,/NO/!d;/%/!d'"
To display on 2 lines:
( F=/etc/screenrc N=c IFS=$'\n'; for L in $(sed 's/%Z./%Z\n/'<<<`stat --h|sed -n '/^ *%/s/^ *%\(.\).*$/\1:%\1/p'`); do G=$(echo "stat -$N '$L' \"$F\""); eval $G; N=fc;done; )
For a similarly powerful stat-like function optimized for pretty output (and can sort by any field), check out the "lll" function
From my .bash_profile ->
http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
Once you get into advanced/optimized scripts, functions, or cli usage, you will use the sort command alot. The options are difficult to master/memorize however, and when you use sort commands as much as I do (some examples below), it's useful to have the help available with a simple alias. I love this alias as I never seem to remember all the options for sort, and I use sort like crazy (much better than uniq for example).
# Sorts by file permissions
find . -maxdepth 1 -printf '%.5m %10M %p\n' | sort -k1 -r -g -bS 20%
00761 drwxrw---x ./tmp
00755 drwxr-xr-x .
00701 drwx-----x ./askapache-m
00644 -rw-r--r-- ./.htaccess
# Shows uniq history fast
history 1000 | sed 's/^[0-9 ]*//' | sort -fubdS 50%
exec bash -lxv
export TERM=putty-256color
Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
This will remove all installed kernels on your debian based install, except the one you're currently using.
From:
http://tuxtweaks.com/2009/12/remove-old-kernels-in-ubuntu/comment-page-1/#comment-1590
Instead of having someone else read you the Digg headlines, Have OSX do it. Requires Curl+Sed+Say. This could probably be easily modified to use espeak for Linux.
The thunderbird message datastores get corrupt some times causing random failures, compaction to fail and general suck in thunderbird. Removing them causes thunderbird to rebuild the indexes and makes things quick again.
Extracts ip addressess from file using sed. Uses a tag(ip) to grep the IP lines after extracting. Must be a way to just output regex matched on sed.
This provides a way to sort output based on the length of the line, so that shorter lines appear before longer lines. It's an addon to the sort that I've wanted for years, sometimes it's very useful. Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
I've wanted this for a long time, finally just sat down and came up with it. This shows you the sorted output of ps in a pretty format perfect for cron or startup scripts. You can sort by changing the k -vsz to k -pmem for example to sort by memory instead.
If you want a function, here's one from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html
aa_top_ps(){ local T N=${1:-10};T=${2:-vsz}; ps wwo pid,user,group,vsize:8,size:8,sz:6,rss:6,pmem:7,pcpu:7,time:7,wchan,sched=,stat,flags,comm,args k -${T} -A|sed -u "/^ *PID/d;${N}q"; }
If you have lots of subversion working copies in one directory and want to see in which repositories they are stored, this will do the trick. Can be convenient if you need to move to a new subversion server.
if you need a quick way of printing out all the packages that contain classes this command will print the directory structure and replace '/' with '.'
It will also ignore CVS directories (we use CVS here)
I like to label my grub boot options with the correct kernel version/build.
After building and installing a new kernel with "make install" I had to edit my grub.conf by hand.
To avoid this, I've decided to write this little command line to:
1. read the version/build part of the filename to which the kernel symlinks point
2. replace the first label lines of grub.conf
grub.conf label lines must be in this format:
Latest [{name}-{version/build}]
Old [{name}-{version/build}]
only the {version/build} part is substituted.
For instance:
title Latest [GNU/Linux-2.6.31-gentoo-r10.201003]
would turn to
title Latest [GNU/Linux-2.6.32-gentoo-r7.201004]"
If you have used bash for any scripting, you've used the date command alot. It's perfect for using as a way to create filename's dynamically within aliases,functions, and commands like below.. This is actually an update to my first alias, since a few commenters (below) had good observations on what was wrong with my first command.
# creating a date-based ssh-key for askapache.github.com
ssh-keygen -f ~/.ssh/`date [email protected]$HOSTNAME-%m-%d-%g` -C '[email protected]'
# /home/gpl/.ssh/[email protected]
# create a tar+gzip backup of the current directory
tar -czf $(date +$HOME/.backups/%m-%d-%g-%R-`sed -u 's/\//#/g' <<< $PWD`.tgz) .
# tar -czf /home/gpl/.backups/04-22-10-01:13-#home#gpl#.rr#src.tgz .
I personally find myself having to reference
date --help
quite a bit as a result. So this nice alias saves me a lot of time. This is one bdash mofo. Works in sh and bash (posix), but will likely need to be changed for other shells due to the parameter substitution going on.. Just extend the sed command, I prefer sed to pretty much everything anyways.. but it's always preferable to put in the extra effort to go for as much builtin use as you can. Otherwise it's not a top one-liner, it's a lazyboy recliner.
Here's the old version:
alias dateh='date --help|sed "/^ *%%/,/^ *%Z/!d;s/ \+/ /g"|while read l;do date "+ %${l/% */}_${l/% */}_${l#* }";done|column -s_ -t'
This trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ]
Ever gone to a site that has an MP3 embedded into a pesky flash player, but no download link? Well, this one-liner will yank the names of those tunes straight out of FF's cache in a nice, easy to read list. What you do with them after that is *ahem* no concern of mine. ;)