Commands by lgallardo (1)

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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

Command to rename multiple file in one go
An entirely shell-based solution (should work on any bourne-style shell), more portable on relying on the rename command, the exact nature of which varies from distro to distro.

Get IP from hostname
Get the IP of a hostname.

Copy a file over SSH without SCP

Edit all files found having a specific string found by grep
The grep switches eliminate the need for awk and sed. Modifying vim with -p will show all files in separate tabs, -o in separate vim windows. Just wish it didn't hose my terminal once I exit vim!!

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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" }

Show the command line for a PID with ps
Show the command line for a PID with ps

Command template, executing a command over multiple files, outputing progress and fails only
This is a command template for achiving the following: * loop over files --> find -name "" | while read file; do ...; done * output progress --> echo -n . * execute some command on each file and save output for later usage --> output=$() * if command failed, open subshell and echo newline --> || (echo;...;...;) * echo output of command --> echo "$output"

Get all files of particular type (say, PDF) listed on some wegpage (say, example.com)
See man wget if you want linked files and not only those hosted on the website.


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