Commands by rdc (9)

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check open ports without netstat or lsof

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" }

list all opened ports on host
in loop, until the last port (65535), list all opened ports on host. in the sample I used localhost, but you can replace with any host to test.

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" }

Filter IPs out of files

syncronizing datas beetween two folder (A and B) excluding some directories in A (dir1 and dir2)

Advanced LS Output using Find for Formatted/Sortable File Stat info
I love this function because it tells me everything I want to know about files, more than stat, more than ls. It's very useful and infinitely expandable. $ find $PWD -maxdepth 1 -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n' | sort -rgbS 50% 00761 drwxrw---x askapache:askapache 777:666 [06/10/10 | 06/10/10 | 06/10/10] [d] /web/cg/tmp The key is: # -printf '%.5m %10M %#9u:%-9g %#5U:%-5G [%AD | %TD | %CD] [%Y] %p\n' which believe it or not took me hundreds of tweaking before I was happy with the output. You can easily use this within a function to do whatever you want.. This simple function works recursively if you call it with -r as an argument, and sorts by file permissions. $ lsl(){ O="-maxdepth 1";sed -n '/-r/!Q1'

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

add a backup (or any other) suffix to a file
Very helpful when you've got complex filenames and needs to change just some small parts of it. Renaming a file called "i-made-a-small-typo-right-here" to "i-made-a-big-typo-right-here": $ mv -vi i-made-a-{small,big}-typo-right-here You could also copy multiple files, edit, remove, process, etc.

Find files containing string and open in vim
I often use "vim -p" to open in tabs rather than buffers.


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