Commands by szimbaro (7)

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Fibonacci numbers with awk
Another combination of seq and awk. Not very efficient, but sufficiently quick.

Function to output an ASCII character given its decimal equivalent

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

Annotate tail -f with timestamps
Uses the command ts in order to add a timestamp on each line. This command is provided in the moreutils package on Debian, and you may need libtime-duration-perl to be able to format the date.

Update a tarball
This will update the tarball, adding files that have changed since the last update. This assumes that the tarball is in the same directory as the files being archived. N.B. This command can't be used on compressed tarballs. N.B. This will add the updated files to the tarball, so that the tarball will have two versions of each file. This will make the tarball larger, but doesn't have any other significant effect.

list files recursively by size

Rank top 10 most frequently used commands

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"

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Create a new file


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