Commands tagged Shell programming (6)

  • Working random fact generator

    Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point. This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact. If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read. wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;" The file lastfact, can then be examined whenever the command fails.


    13
    wget randomfunfacts.com -O - 2>/dev/null | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;"
    tali713 · 2010-03-30 23:49:30 81
  • Simple XML tag extract with sed

    Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line. If nobody posts an alternative for the multiline sed version, I'll figure it out later...


    4
    sed -n 's/.*<foo>\([^<]*\)<\/foo>.*/\1/p'
    recursiverse · 2009-07-23 07:59:30 3
  • Alias to edit and source your .bashrc file

    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


    2
    alias vb='vim ~/.bashrc; source ~/.bashrc'
    haivu · 2009-03-02 21:01:49 8
  • Working random fact generator

    extension to tali713's random fact generator. It takes the output & sends it to notify-osd. Display time is proportional to the lengh of the fact.


    2
    wget randomfunfacts.com -O - 2>/dev/null | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;" | while read FUNFACT; do notify-send -t $((1000+300*`echo -n $FUNFACT | wc -w`)) -i gtk-dialog-info "RandomFunFact" "$FUNFACT"; done
    mtron · 2010-04-02 09:43:32 4
  • Display all shell functions set in the current shell environment

    Uses the shell builtin `declare` with the '-f' flag to output only functions to grep out only the function names. You can use it as an alias or function like so: alias shfunctions="builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'" shfunctions () { builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'; } Show Sample Output


    2
    builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'
    sciro · 2018-07-23 05:24:04 1018
  • Working random fact generator

    This is a working version, though probably clumsy, of the script submitted by felix001. This works on ubuntu and CygWin. This would be great as a bash function, defined in .bashrc. Additionally it would work as a script put in the path. Show Sample Output


    0
    lynx -dump randomfunfacts.com | grep -A 3 U | sed 1D
    xizdaqrian · 2009-05-05 07:52:10 12

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Remove a range of lines from a file
Delete a range of line

Query Wikipedia via console over DNS
Query Wikipedia by issuing a DNS query for a TXT record. The TXT record will also include a short URL to the complete corresponding Wikipedia entry.You can also write a little shell script like: $ $ cat wikisole.sh $ #!/bin/sh $ dig +short txt ${1}.wp.dg.cx and run it like $ ./wikisole.sh unix were your first option ($1) will be used as search term.

Equivalent to ifconfig -a in HPUX
Command is properly working on HP-UX 11.31

grab all commandlinefu shell functions into a single file, suitable for sourcing.
Each shell function has its own summary line, as a comment. If there are multiple shell functions with the same name, the function with the highest number of votes is put into the file. Note: added 'grep -v' to the end of the pipeline, to eliminate extraneous lines containing only '--'. Thanks to matthewbauer for pointing this out.

Rename many files in directories and subdirectories
This is probably overkill, but I have some issues when the directories have spaces in their names. The $ find . -type d -print0 | while read -d $'\0' dir; do xxx; done loops over all the subdirectories in this place, ignoring the white spaces (to some extend). $ cd "$dir"; echo " process $dir"; cd -; goes to the directory and back. It also prints some info to check the progress. $ find . -maxdepth 1 -name "*.ogg.mp3" -exec rename 's/.ogg.mp3/.mp3/' {} \; renames the file within the current directory. The whole should work with directories and file names that include white spaces.

Update your OpenDNS network ip
Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP. For getting your IP, you can use one of the many one-liners here on commandlinefu. Example: I use this in a script which is run by kppp after it has successfully connected to my ISP: --- #!/bin/bash IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`" PW="hex-obfuscated-pw-here" if [ "$IP" == "" ] ; then echo 'Not online.' ; exit 1 else wget -q --user=topsecret --password="`echo $PW | xxd -ps -r`" 'https://updates.opendns.com/nic/update?hostname=myhostname&myip='"$IP" -O - /etc/init.d/ntp-client restart & fi --- PS: DynDNS should use a similar method, if you know the URL, please post a comment. (Something with members.dyndns.org, if I recall correctly)

Multiple variable assignments from command output in BASH
This version uses read instead of eval.

scroll file one line at a time (w/only UNIX base utilities)
usage examples ls largedir |rd lynx -dump largewebsite.com |rd rd < largelogfile

Log the current memory statistics frequently to syslog
Uses logger in a while loop to log memory statistics frequently into the local syslog server.

Lookup your own IPv4 address

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