How to find home
note: as a user of the system you will be given a user directory under the Users directory
$ echo $HOME
How to go to the home directory choices:
$ cd $HOME, $ cd ~, $ cd, and
$ cd then drag your home directory from your Finder window
How to go to the root directory
note: when you see pathnames as such Users/patrick/Documents, this is an “absolute” path name starting at the root
$ cd /
How to print your working/current directory
note: every terminal window operates an independent working directory
$ pwd
How to list your files
$ ls
$ ls -F – this will append a forward slash (/) to directories, an asterisk (*) to executables or scripts, an (@) to symbolic links
$ ls -al – this will show the “long” version of “all” files in the directory
file permissions are shown on the first column in a super cryptic way like this (feel free to skip this portion:
drwxr-xr-xthese are:
file type (1 char) – here “d” is directory, “-” would’ve meant file
owners file permission (3 char) – the owner has read, write, executable permissions on this directory
group file permission (3 char) – everyone in this users group has read and executable permissions
others file permission (3 char) – everyone on the computer in any group has read and execute permissions
How to see the disk usage of:
$ du Documents/Outline.doc (size of a file in 512-byte blocks)
$ du -s Documents (summary size of the directory in 512 byte blocks)
$ du -sh Documents (summary size of the directory in human readable format)
How to see the remaining free disk space
$ df -H (human readable disk free space using base 10 to calculate sizes)
How to change the permissions on files and directories
$ chmod "categories" "add/subtract" "permissions" "filename"
The categories permission options are:
u owner, g groups, o others, and
a – all permissions, owner, groups and others
The add/subtract options are:
+ adding, - subtracting
The permission options are:
r read, w write, x execute
Examples:
How to delete your user permission from removing the files within a directory (write access)
$ chmod u-w dirname
How to delete all permissions from removing the files within a directory (write access)
$ chmod a-w dirname
removing write access on a file does not stop it from being removed, you must remove write access to the directory to protect the file from deletion – Ice Bear
How to change the owner of a file or directory
$ chown some_name filename