Commands by pillo (1)

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Add timestamp to history
History usually only gives the command number and the command. This will add a timestamp to the history file. Note: this will only put the correct timestamp on commands used after the export is done. You may want to put this in your .bashrc

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

Write on the console without being registered
just use a space to prevent commands from being recorded in bash's history on most systems

combining streams
2>&1 permit to combinate stdout and stderr. grep will catch stderr and stdout instead of stdout only.

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" }

Check if a remote port is up using dnstools.com (i.e. from behind a firewall/proxy)
Shell function; returns 0 if the port is up, 1 otherwise (check $? after executing). First parameter: IP address/hostname Second parameter: port number There is no error checking for the input parameters.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Extract the contents of an RPM package to your current directory without installing them.
This assumes you have the 'rpm', 'rpm2cpio' and 'cpio' packages installed. This will extract the contents of the RPM package to your current directory. This is useful for working with the files that the package provides without installing the package on your system. Might be useful to create a temporary directory to hold the packages before running the extraction: $ mkdir /tmp/new-package/; cd /tmp/new-package

Hardlink all identical files in the current directory (regain some disk space)
Meaning of switches (see man page too): v verbose p ignore mode (permissions) o ignore owner, group t ignore time of modification Disadvantage: If you modify any linked file, this will propagate to all other files which occupy the same space.

Delete all but the latest 5 files, ignoring directories


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