Commands using echo (1,545)

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Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

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"

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

Stream audio over ssh
This one doesn't need to convert to wav.

Plaintext credentials sniffing with tcpdump and grep
Simple TCPDUMP grepping for common unsafe protocols (HTTP, POP3, SMTP, FTP)

tar and remove files which are older that 100 days
tar does not have a -mtime option as find. tar appends all the file to an existing tar file.

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"

Scan for new SCSI devices
Issues a scan command on the given scsi host adapter (ex. a fibre channel adapter, in the example above on host0). Output can be watched in the messages log or in "dmesg"

Remove Thumbs.db files from folders
An alternative which uses the advanced zsh globbing (pattern matching)

Start a command on only one CPU core
This is useful if you have a program which doesn't work well with multicore CPUs. With taskset you can set its CPU affinity to run on only one core.


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