Commands by keymon (18)

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Find the package a command belongs to on debian-based distros
Advanced revision to the command 8776 . This revision follows symbolic links. The quotation-marks surrounding $(which $1) allows for graceful handling of errors ( ie. readlink does not complain incase 'which' command generates (null) output)

Replace space in filename
This commands removes space from all the files with specific extension. I've specifed *.jpg as an example.

Setting reserved blocks percentage to 1%
According to tune2fs manual, reserved blocks are designed to keep your system from failing when you run out of space. Its reserves space for privileged processes such as daemons (like syslogd, for ex.) and other root level processes; also the reserved space can prevent the filesystem from fragmenting as it fills up. By default this is 5% regardless of the size of the partition. http://www.ducea.com/2008/03/04/ext3-reserved-blocks-percentage/

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Monitor a file with tail with timestamps added
Should be a bit more portable since echo -e/n and date's -Ins are not.

export iPad App list to txt file
This will generate the same output without changing the current directory, and filepath will be relative to the current directory. Note: it will (still) fail if your iTunes library is in a non-standard location.

Get your external IP address if your machine has a DNS entry
Using DynDNS or a similar service not only allows access to your home machine from outside without needing to know what IP the ISP has assigned to it but it also comes in handy if you want to know your external IP address. The only purpose of the sed command is to remove the leading "host.na.me has address " part from the output. If you don't need to discard it you can simply use $ host $HOSTNAME

Realtime apache hits per second
Change the cut range for hits per 10 sec, minute and so on... Grep can be used to filter on url or source IP.

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


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