Commands using time (30)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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List all NPM global packages installed

Grab the first 3 octets of your ip addresses
For machines that have many ip blocks spanning different Class C's, this will show which ones.

Using numsum to sum a column of numbers.
numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at It contains about 10 different programs for dealing with numbers from the command line. Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.

Vectorize xkcd strips
Uses ImageMagick and potrace to vectorize the input image, with parameters optimized for xkcd-like pictures.

Remount an already-mounted filesystem without unmounting it
Necessary for fsck for example. The remount functionality follows the standard way how the mount command works with options from fstab. It means the mount command doesn't read fstab (or mtab) only when a device and dir are fully specified. After this call all old mount options are replaced and arbitrary stuff from fstab is ignored, except the loop= option which is internally generated and maintained by the mount command. It does not change device or mount point.

Recall last argument of previous command
!$ recalls the last argument of the previous command. This is very useful when you have to operate several operations on the same file for example.

Route outbound SMTP connections through a addtional IP address rather than your primary

Remove a line from a file using sed (useful for updating known SSH server keys when they change)
remove the host for the .ssh/know_host file

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

Display the human-readable sizes of all files and folders in the current directory with 3 decimal places
To sort the list by file/directory size, insert `sort -n |` before `awk`.

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