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Create a bash script from last n commands
Uses history to get the last n+1 commands (since this command will appear as the most recent), then strips out the line number and this command using sed, and appends the commands to a file.

grep for minus (-) sign
Use flag "--" to stop switch parsing

Length of longest line of code
Here's an awk version.

Search google and show only urls
Get the first 10 google results form a querry, but showing only the urls from the results. Use + to search diferent terms, ex: commandlinefu+google .

List all active access_logs for currently running Apache or Lighttpd process
Ever logged into a *nix box and needed to know which webserver is running and where all the current access_log files are? Run this one liner to find out. Works for Apache or Lighttpd as long as CustomLog name is somewhat standard. HINT: works great as input into for loop, like this: $ for i in `lsof -p $(netstat -ltpn|awk '$4 ~ /:80$/ {print substr($7,1,index($7,"/")-1)}')| awk '$9 ~ /access.log$/ {print $9| "sort -u"}'` ; do echo $i; done Very useful for triage on unfamiliar servers!

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Get video information with ffmpeg
I used an flv in my example, but it'll work on any file ffmpeg supports. It says it wants an output file, but it tells what you want to know without one.

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

Gets directory and files tree listing from a FTP-server
Creates a file with contents like `du -a`, only it is remote server filesystem hierarchy. Very usefull then for grep-ing without remote connection.

Edit a PDF's metadata using exiftool
Edit the pdf file foo.pdf's metadata. -overwrite_original overwrites the original file (w/o it exiftool creates a new file)


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