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Commands tagged bash from sorted by
Terminal - Commands tagged bash - 694 results
^Z $bg $disown
2009-03-17 21:52:52
User: fall0ut
47

You're running a script, command, whatever.. You don't expect it to take long, now 5pm has rolled around and you're ready to go home... Wait, it's still running... You forgot to nohup it before running it... Suspend it, send it to the background, then disown it... The ouput wont go anywhere, but at least the command will still run...

ctrl-z
2009-03-16 20:58:31
User: mallegonian
Tags: bash hotkey
11

Hold ctrl and press z to pause the current thread. Run

fg

to resume it.

sort file1.txt | uniq > file2.txt
find . -print | sed -e 's;[^/]*/;|____;g;s;____|; |;g'
2009-03-12 22:25:26
Functions: find sed
-1

NOT MINE! Taken from hackzine.com blog.

It creates a tree-style output of all the (sub)folders and (sub)files from the current folder and down(deeper)

Quoting some of hackzine's words

"Murphy Mac sent us a link to a handy find/sed command that simulates the DOS tree command that you might be missing on your Mac or Linux box. [..split...] Like most things I've seen sed do, it does quite a bit in a single line of code and is completely impossible to read. Sure it's just a couple of substitutions, but like a jack in the box, it remains a surprise every time I run it."

echo -n $HEXBYTES | xxd -r -p | dd of=$FILE seek=$((0x$OFFSET)) bs=1 conv=notrunc
2009-03-11 17:02:24
User: zombiedeity
Functions: dd echo
2

Replace (as opposed to insert) hex opcodes, data, breakpoints, etc. without opening a hex editor.

HEXBYTES contains the hex you want to inject in ascii form (e.g. 31c0)

OFFSET is the hex offset (e.g. 49cf) into the binary FILE

export PS1='\n[\u@\h \! \w]\n\[\e[32m\]$ \[\e[0m\]'
2009-03-09 15:34:22
User: haivu
Functions: export
Tags: bash
7

I put that line in my .bash_profile (OS X) and .bashrc (Linux).

Here is a summary of what the \char means: n=new line, u=user name, h=host, !=history number, w=current work directory

The \[\e[32m\] sequence set the text to bright green and \[\e[0m\] returns to normal color.

For more information on what you can set in your bash prompt, google 'bash prompt'

i="8uyxVmdaJ-w";mplayer -fs $(curl -s "http://www.youtube.com/get_video_info?&video_id=$i" | echo -e $(sed 's/%/\\x/g;s/.*\(v[0-9]\.lscache.*\)/http:\/\/\1/g') | grep -oP '^[^|,]*')
2009-03-09 03:57:44
User: lrvick
Functions: echo grep sed
56

This is the result of a several week venture without X. I found myself totally happy without X (and by extension without flash) and was able to do just about anything but watch YouTube videos... so this a the solution I came up with for that. I am sure this can be done better but this does indeed work... and tends to work far better than YouTube's ghetto proprietary flash player ;-)

Replace $i with any YouTube ID you want and this will scrape the site for the _real_ URL to the full quality .FLV file on Youtube's server and will then will hand that over to mplayer (or vlc or whatever you want) to be streamed.

In some browsers you can replace $i with just a % or put this in a shell script so all YouTube IDs can be handed directly off to your media player of choice for true streaming without the need for Flash or a downloader like clive. (I do however fully recommend clive if you wish to archive videos instead of streaming them)

If any interest is shown I would be more than happy to provide similar commands for other sites. Most streaming flash players use similar logic to YouTube.

Edit: 05/03/2011 -

Updated line to work with current YouTube. It could be a lot prettier but I will probably follow up with another update when I figure out how to get rid of that pesky Grep. Sed should take that syntax... but it doesn't.

Original (no longer working) command:

mplayer -fs $(echo "http://youtube.com/get_video.php?$(curl -s $youtube_url | sed -n "/watch_fullscreen/s;.*\(video_id.\+\)&title.*;\1;p")")

tail -f *[!.1][!.gz]
2009-03-06 16:24:44
User: piscue
Functions: tail
5

with discard wilcards in bash you can "tail" newer logs files to see what happen, any error, info, warn...

echo 1 2 3 > FILE; while read -a line; do echo ${line[2]}; done < FILE
2009-03-06 15:32:40
User: occam
Functions: echo read
Tags: bash
-2

This will print out the third column of every line in FILE. Useful for many files in /proc or *csv data.

find . -type d \( -name DIR1 -o -name DIR2 \) -prune -o -type f -print0 | xargs -r0 md5sum
2009-03-05 21:26:24
User: starchox
Functions: find xargs
Tags: bash
4

Useful if you want get all the md5sum of files but you want exclude some directories. If your list of files is short you can make in one command as follow:

find . -type d \( -name DIR1 -o -name DIR2 \) -prune -o -type f -exec md5sum {} \;

Alternatively you can specify a different command to be executed on the resulting files.

alias lh='ls -a | egrep "^\."'
ifconfig -a | nawk 'BEGIN {FS=" "}{RS="\n"}{ if($1~ /:/) {printf "%s ", $1}}{ if($1=="inet") {print " -- ",system("arp "$2)}}'|egrep -v "^[0-9]$"
2009-03-02 23:15:13
User: leprasmurf
Functions: ifconfig
1

Needed to get the Mac of various devices on a solaris box, but didn't have root. This command used awk to display the Network device, the IP, and the MAC a line at a time.

alias vb='vim ~/.bashrc; source ~/.bashrc'
2009-03-02 21:01:49
User: haivu
Functions: alias col groff man
2

Place the line above in your ~/.bahsrc file. Now every time you issue the 'vb' command, you invoke the vim editor to edit it, then source it so the changes take effect immediately.

Notes:

* This mechanism is not working well if your .bashrc contains commands that should not be sourced more than once.

* This trick also work for your csh or tclsh users: place the following line in your ~/.cshrc file:

alias vc 'vim ~/.cshrc; source ~/.cshrc

Thank you adzap for pointing out the missing quote

tail -f file1 (file2 .. fileN)
2009-03-02 11:13:42
User: hberth
Functions: tail
Tags: bash Ubuntu
3

Useful to e.g. keep an eye on several logfiles.

export IFS=$'\n';for dir in $( ls -l | grep ^d | cut -c 52-);do du -sh $dir; done
lynx -dump http://www.ip-adress.com/ip_tracer/?QRY=$1|grep address|egrep 'city|state|country'|awk '{print $3,$4,$5,$6,$7,$8}'|sed 's\ip address flag \\'|sed 's\My\\'
2009-02-25 17:16:56
User: leftyfb
Tags: bash
24

I save this to bin/iptrace and run "iptrace ipaddress" to get the Country, City and State of an ip address using the http://ipadress.com service.

I add the following to my script to get a tinyurl of the map as well:

URL=`lynx -dump http://www.ip-adress.com/ip_tracer/?QRY=$1|grep details|awk '{print $2}'`

lynx -dump http://tinyurl.com/create.php?url=$URL|grep tinyurl|grep "19. http"|awk '{print $2}'

svn st | grep ^? | xargs svn add 2> /dev/null
TMPROOT=/tmp; TMPDIR=$(mktemp -d $TMPROOT/somedir.XXXXXX); TMPFILE=$(mktemp $TMPROOT/somefile.XXXXXX); trap "rm -rf $TMPDIR $TMPFILE; exit" INT TERM EXIT; some treatment using $TMPDIR and $TMPFILE; exit 0
2009-02-24 09:35:22
User: raphink
Functions: exit mktemp trap
2

Cleanly create tempfiles using mktemp and remove them using traps instead of removing them in the end of the script. This way, you make sure the tempfiles are removed properly even if the script is killed or interrupted.

For a user script in KDE4, you can set TMPROOT using :

TMPROOT=$(kde4-config --path tmp)
FLOOR=0; RANGE=10; number=0; while [ "$number" -le $FLOOR ]; do number=$RANDOM; let "number %= $RANGE"; done; echo $number
2009-02-20 09:33:56
User: raphink
Functions: echo
Tags: bash
-1

This one-liner outputs a random number between the values given for FLOOR and RANGE.