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Site by David Winterbottom (user root).

Commands by DaveQB

Commands by DaveQB from sorted by
Terminal - Commands by DaveQB - 9 results
watch -n1 'date "+%T"'
2011-02-16 00:33:51
User: DaveQB
Functions: watch
4
Up
Down
Console clock

A console clock with the current time.

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df /media/mountpoint |egrep -o '^[/a-z0-9]*'
2011-01-24 21:14:55
User: DaveQB
Functions: df egrep
Tags: grep,df
-1
Up
Down
find the device when you only know the mount point

Shorter way to find the device for a given mountpoint

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sed '/'"<opening tag>"'/,/'"<closing tag>"'/{/'"<closing tag>"'/d;p};d' "<file>"
2010-11-08 21:43:00
User: DaveQB
Functions: sed
Tags: grep tag filter multiline
1
Up
Down
Multi line grep using sed and specifying open/close tags

This line does not include your closing tag in the output.

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find * -maxdepth 1 -type f ! -name abc -delete
2010-07-19 00:29:59
User: DaveQB
Functions: find
5
Up
Down
Remove all the files except abc in the directory

Finds all files in the current directory and deletes them besides file called "abc"

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echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi
2010-07-11 23:09:11
User: DaveQB
Functions: echo egrep exit printf sed
Tags: sed
-12
Up
Down
Remove "ssh host" from known hosts file.

I have this as a file called deletekey in my ~/bin.

Makes life a little easier.

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free -m | awk '/buffer/ {print $4}'
2010-06-27 23:30:27
User: DaveQB
Functions: awk free
Tags: ram free
3
Up
Down
Print number of mb of free ram

Here we instead show a more real figure for how much free RAM you have when taking into consideration buffers that can be freed if needed.

Unix machines leave data in memory but marked it free to overwrite, so using the first line from the "free" command will mostly give you back a reading showing you are almost out of memory, but in fact you are not, as the system can free up memory as soon as it is needed.

I just noticed the free command is not on my OpenBSD box.

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cd /some/empty/folder/website_diffs/sitename && wget -N http://domain.com/ 2>&1 |grep -q "o newer" || printf "Sites web page appears to have updated.\n\nSuggest you check it out.\n\n"|mail -s "Sites page updated." david@email.com
2010-05-09 07:28:42
User: DaveQB
Functions: cd grep mail printf wget
2
Up
Down
Email someone if a web page has been updated.

A cronjob command line to email someone when a webpages homepage is updated.

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date +%A | cut -c $(( $(date +%A | wc -c) - 1 ))
2010-04-07 00:23:15
User: DaveQB
Functions: cut date wc
Tags: bash echo cut date wc
0
Up
Down
Bash function to see what the day ends in

A command to find out what the day ends in. Can be edited slightly to find out what "any" output ends in.

NB: I haven't tested with weird and wonderful output.

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INPUT=<input_video> && ffmpeg -i "$INPUT" -vn -f wav - | oggenc -o ${INPUT%%.*}.ogg -
2009-05-19 07:57:43
User: DaveQB
1
Up
Down
Convert a videos audio track to ogg vorbis.

Assumes you have ffmpeg and oggenc.

Similar to other scripts here, but this time outputting to Ogg Vorbis.

I added the variable assignment for a nice output name.

This is part of an interactive bash script I have with a few little multimedia tasks in it.

http://www.dward.us/software/VSAK.sh

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