Commands by aaronjcopley (1)

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Install pip with Proxy
Installs pip packages defining a proxy

cat stdout of multiple commands
Concatenate the stdout of multiple commands.

archlinux:Delete packages from pacman cache that are older than 7 days
Sometimes my /var/cache/pacman/pkg directory gets quite big in size. If that happens I run this command to remove old package files. Packages that we're upgraded in last N days are kept in case you are forced to downgrade a specific package. The command is obviously Arch Linux related.

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

Open a manpage in the default (graphical) web browser
An easy alias for opening a manpage, nicely HTML formatted, in your set internet browser. If you get a "command exited with status 3" error you need to install groff.

Rot13 using the tr command
rot13 maps a..mn..z (A..MN..Z) to n..za..m (n..za..m) and so does this alias.

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"

Use bash history with process substitution
Bash has a great history system of its commands accessed by the ! built-in history expansion operator (documented elsewhere on this site or on the web). You can combine the ! operator inside the process redirection

list files recursively by size

Download files linked in a RSS feed
The difference between the original version provided and this one is that this one works rather than outputting a wget error

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