Commands by programmer (5)

  • Create a bash script to change the modification time for each file in 'files.txt' such that they are in the same order as in 'files.txt' File name for bash script specified by variable, 'scriptName'. It is made an executable once writing into it has been completed. Show Sample Output


    1
    scriptName="reorder_files.sh"; echo -e '#!/bin/sh\n' > "${scriptName}"; cat files.txt | while read file; do echo "touch ${file}; sleep 0.5;" >> "${scriptName}"; done; chmod +x "${scriptName}";
    programmer · 2016-04-19 11:52:00 4
  • Removing Course name prefix added Show Sample Output


    1
    ls *.pdf | while read file; do newfile="${file##CS749__}"; mv "${file}" "${newfile}"; done;
    programmer · 2016-04-19 11:06:43 11
  • Adding course name prefix to lecture pdfs Show Sample Output


    1
    ls *.pdf | while read file; do newfile="CS749__${file}"; mv "${file}" "${newfile}"; done;
    programmer · 2016-04-19 11:04:47 4
  • retrieve file names back from touch commands for them Show Sample Output


    1
    touch files.txt; cat reorder_files.sh | while read line; do x=`echo $line | sed 's/touch \([a-z0-9\.]\+.*.pdf\);.*/\1/'`; echo $x >> files.txt ; done;
    programmer · 2016-04-19 11:01:17 1
  • useful to find the list of dependencies Show Sample Output


    2
    jar -tf file.jar
    programmer · 2010-10-13 10:53:07 0

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The wisdom of Cave Johnson
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add all files not under version control to repository
checks which files are not under version control, fetches the names and runs them through "svn add". WARNING: doesn't work with white spaces.

Find directory depth
Returns a the directory depth.

resolve hostname to IP our vice versa with less output
inverted version: resolveip -s 216.34.181.xxx freshmeat.net

Get your commandlinefu points (upvotes - downvotes)
This version prints current votes and commands for a user. Pass the user as an argument. While this technically "fits" as a one liner, it really is easier to look at as a shell script with extra whitespace. :)

python smtp server
This command will start a simple SMTP server listening on port 1025 of localhost. This server simply prints to standard output all email headers and the email body.

ssh and attach to a screen in one line.
If you know the benefits of screen, then this might come in handy for you. Instead of ssh'ing into a machine and then running a screen command, this can all be done on one line instead. Just have the person on the machine your ssh'ing into run something like $ screen -S debug Then you would run $ ssh -t user@host screen -x debug and be attached to the same screen session.

Install pip with Proxy
Installs pip packages defining a proxy

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Network traffic on NICs in mbps without sar, iperf, etc...
Need output in mbps (bits) # ./bytes-second.sh eth0 eth0 interface maximum Speed: 1000Mb/s RX:12883212 TX:17402002 B/s | RX:98 TX:132 Mb/s RX:12371647 TX:17830111 B/s | RX:94 TX:136 Mb/s RX:12502750 TX:17860915 B/s | RX:95 TX:136 Mb/s


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