Securely transferring files between hosts with SCP

scp (or “secure copy“) is a method of securely transferring files between two hosts. Unlike wget, the files to be transferred do not need to be publicly accessible via either HTTP or FTP. To put it another way, ssh + cp = scp. Some caveats: You must specify a target file. If you don’t, scp […]

Generating a password-protected archive

Generating an archive file from either a file or directory is a cinch using the command-line. Here’s the structure: zip [options] [archive name] [file or folder to be archived] While there are many options available, the one we’re interested in is -e, for “encrypted”, like so: zip -e example.txt To create a password-protected archive […]

Using “du” to determine directory size

The *nix command ls returns lots of useful information, particularly with the -alh flags, to display permissions, owner, group, modification date, file name, and human-readable size for all files and directories within the current directory. Well, sort of. It falls short on directory size, treating the directory like a file and returning only the size […]

Changing ownership with chown

Need to CHange the OWNer of a file or directory? chown [new owner] [file or directory] If, for example, I wanted to change the owner of /var/www/vhosts/my_website/tmp to “root” I’d run this: chown root /var/www/vhosts/my_website/tmp If you want to apply the ownership change recursively — that is, to all subdirectories and/or files within — add […]

Removing a non-empty directory

It’s fine to use rmdir [dir name] for empty directories. But if you’re looking to remove a non-empty directory, you need recursion: rm -rf [dir name] Use with caution — you will not be prompted to verify!

Changing permissions with chmod

Here’s the syntax for CHanging permissions or MODe — also known as chmod — for files and directories: chmod [permissions] /path/to/file/or/directory The three possible users are: file owner group of authorized users everyone else (a.k.a. “the world”) The possible actions (and associated binary values) are: 4: read 2: write 1: execute Total the values for […]