Linux and Windows systems both allow ambiguous filenames, which use wildcard symbols to enable filename matching. The process of converting an ambiguous filename, or filename pattern, into a list of matching filenames is called globbing or filename expansion.
On a Linux system, globbing is performed by the shell. This means that all arguments are subject to globbing, whether they're intended to be a filename argument or not.
On a Windows system, ambiguous filenames are converted into a list of filenames by the command or application. This means that arguments that are not filenames are not subject to filename expansion. However, it also means that applications must contain additional code to perform globbing.
| Symbol | Meaning in Linux | Meaning in Windows |
|---|---|---|
| * | Matches zero or more characters | Matches zero or more characters |
| ? | Matches one character | Matches one character, unless at the end of the filename or immediately before the dot preceeding the extension in which case it matches zero or one character |
| [list] or [range] | Matches any one of the characters within the brackets (note that it matches exactly one of the characters) | Not applicable |
| Pattern | Matches on Linux | Does not match on Linux | Matches on Windows | Does not match on Windows |
|---|---|---|---|---|
| *.html | first.html blue.html | RED.HTML purple.htm | Blue.html blue.html RED.HTML | purple.htm |
| a* | a aa aaa alpha argonaut | Alpha banana | a aa aaa alpha Alpha | banana |
| b*e | blue bite | red green blot | blue bite | red green blot |
| c[oa]t | cat cot | coat | cat cot coat (Not applicable) | |
| d?e | due doe | duo Doe date | due doe Doe | duo date |
| a?? | aaa abc | aa abcd | aaa abc aa | abcd |
Therefore the command
del *.pdf
on Windows, or
rm *.pdf
on Linux will remove all files in the current directory that have the extension .pdf
You can combine absolute, relative, or relative-to-home pathnames with patterns. For example, in the command:
del \Users\jdoe\Documents\*.txt
The pattern \Users\jdoe\Documents\*.txt will match all files with a txt extension in the \Users\jdoe\Documents\ directory, and the del command will then attempt to delete all of the matching files.
On Linux, you can also use patterns to match directory names:
rm /home/chris/ops102/*/info.pdf
This will delete any files named info.pdf within any subdirectory of /home/chris/ops102/
Here are some basic commands useful for managing the filesystem and performing basic tasks:
| Linux | Windows | Description |
|---|---|---|
| ls | dir | Lists the contents of a directory – by default, the current directory, or the directories specified as arguments (or a specific file, if specified). |
| echo | echo | Places a message on the screen (the message is given as positional arguments) |
| cal | Displays a simple calendar | |
| date | date /t time /t | Tells you the current date (or date/time) |
| who | quser | Displays information about the logged in user(s) |
| whoami | whoami | Displays the name of the current user |
| clear | cls | Clears the screen (terminal). Note: in the Bash shell, you can also clear the screen during command entry by typing Ctrl+L |
| tree | tree | Displays a “tree view” of the filesystem hierarchy starting at the current directory (or the given directory, if an argument is provided). |
| mkdir | mkdir | Make a directory/folder |
| rmdir | rmdir | Remove a directory/folder |
| rm | del | Removes/deletes one or more files. Specify -rf to recursively force delete a directory and its contents on Linux, or /s to recursively delete a directory and its contents on Windows. |
| X: | (Where X is a drive letter) Switches to the selected drive. | |
| cd | cd | Changes to the given directory, if one is given. If no directory is given, displays the current directory (Windows) or changes to your home directory (Linux). On Windows, a drive designator may be provided, in which case the current directory will be set on the indicated drive. |
| pwd | cd | Prints the current working directory. |
| cp | copy | Copy one or more files to a new name/location. |
| mv | move | Moves a file from one directory to another. |
| mv | ren rename | Renames a file (on Linux, the filename and location are considered to be the same thing) |
| cat | type | Dumps the contents of a text file on the terminal (if there is a lot of text, the display will scroll; if the file is a non-text file, the results are undefined!) |
| more less | more | Displays a file one screen at a time. (Linux: the less command is a more powerful version of the more command, which allows things like scrolling backwards) |
| cut | Selects specific columns from a text file | |
| sort | sort | Sorts a text file |
| diff | comp fc | Shows the differences between (text) files |
| uniq | Displays identical consequtive lines only once | |
| tr | Translates/replaces/deletes occurrences of characters | |
| grep | find | Searches files for text |
| find | Searches for files | |
| touch | copy NUL: filename | Creates an empty file (Linux: if the file exists, touch will just update the date/time of modification). |
To find a Linux command to perform a particular function, use the apropos or man -k commands to search the online documentation. For example, to see commands related to “calendar”:
apropos calendar
man -k calendar # same as the above!
To view information about a Linux command, use the online manual (“manpages”), accessed with the man command:
man commandname
For example, to view the online manual page for cp, enter the command:
man cp
On Windows, you can see a list of commonly used commands by typing
help
To view information about a Windows command, use the online help:
help commandname
For example, to view the online help for dir, enter the command:
help dir
Alternately, to get a brief help summary for a command, enter the name of the command followed by /? – for example, to get a help summary for the copy command, type
copy /?
It's often necessary to edit a text file containing a script, program, data, or configuration information. There are many text editors available.
It is often useful to learn how to use the text editor(s) provided by default with each operating system, because these editors will be available on almost any computer you use without installing any additional software.
On Linux systems, most distributions (the organizations or companies responsible for maintaining and distributing the system) have standardized on the nano editor as the default CLI/TUI text editor (replacing the less-user-friendly but more-powerful vi editor). To start nano, type nano and optionally provide a filename:
nano
nano file
Nano provides a help display at the bottom of the screen. The carat ^ symbol indicates the control key, so the help text “^X Exit” means that you would press Ctrl-X to exit from the editor.
Since Linux systems provide multiple desktop GUI environments, the default GUI text editor(s) will vary with the installed desktop GUI. For example, on Linux desktops using the Gnome environment, the default GUI text editor is Gedit or Gnome Text Editor; on Linux desktops using the KDE desktop, the default GUI text editor is Kate.
The current versions of Windows (Windows 10 & 11) do not provide a CLI/TUI text editor (previous versions of Windows did provide a CLI text editor, and there is a current discussion about ading this back in). However, you can run the GUI Notepad editor, either from the Start Menu, or from the command line (as long as you are not accessing the Windows system remotely through a non-graphical connection):
notepad
notepad file
There are many other text editors available for both platforms, and many editors are available that work on multiple operating systems. For example, nano and vi are available for Windows systems, and editors similar to notepad are available on Linux.
There are also several categories of software that are (arguably) a type of text editor, including:
Software developers and system administrators have strong opinions about their tools, and particularly about their text editors. Things to consider when selecting any type of text editor include:
Most software developers and system administrators use multiple editors for different tasks - for example, they may choose one editor for quick cnfiguration changes, another editor (or IDE) for larger development tasks, and multiple editors for different types of documentation.
Note that features intended for one editing task can be a nuscience in another context. For example, a word processor will often convert double quote characters into “smart quotes” (look closely at the quotation characters in this line), where the opening and closing quote characters are distinct characters. While these look great and are good for general writing, they are problematic in code and in examples that may appear in documentation, because they will be rejected by some types of software which expect straight double-quotes (such as most shells).