locate *.htm?
This command will show all filenames in the current directory that start with "a" or "b", or any capital letter:
ls [abA-Z]*
This command will list any file starting with "a" and ending with "n"
ls a*n
4.1.1.1 Command line autocompletion
This is a great command line feature--I use the [Tab] key a lot to save on typing. It makes it brisk to deal with long and complicated filenames. For example using such a filename on the command line is really not a problems, if I use autocompletion:
dir Eurosong\ 2000\ Olson\ Brothers\ -\ Fly\ on\ the\ wings\ of\ love\ \(denmark\).mp3
I just type
dir Eu<Tab>
and if there are no other files starting with "Eu", the rest of the filename is automatically typed for me. Otherwise, I would have to look at my choices (which are printed for me) and type one or two more characters to make the filename unambiguous. The backslashes in the name of the example song above show that the spaces are "literal", i.e., they spaces are part of the filename.
4.1.1.2 Problems with weird filenames
Most of these problems can be solved using autocompletion. Additionally, to manipulate files with names that do contain metacharacters, I may use a pair of ' ' (two apostrophes), so that the metacharacters are quoted and therefore the shell does not interpret their meaning. For example, to rename a file my file* (contains space and asterisk), I would issue:
mv 'my file*' filename_without_weird_characters.txt
Please note that I use a pair of ' (apostrophes) for quoting. Quoting with a pair of " " (quotation marks) is generally weaker than quoting with ' ' . If you use " (quotation marks) some metacharacters may get interpreted by the shell (altering their meaning).
Following UNIX tradition, on Linux, one may create files with names containing almost any character, including non-printable (control) characters. Those are very infrequent, but if you encounter such a file, it can make you feel really weird. I would rename such a file using a carefully positioned metacharacter. I would use ls first to try if my action indeed targets the desired file, and then rename the file (using the move "mv" command):
ls -l myfile*y.html
mv myfile*y.html myfile.html
(I assume that the non-standard character(s) are between the letters e and y.)
As an example of the perhaps weirdest problems that you might face when using non-recommended characters in a filename, try creating a file with a name starting with a dash and then remove it--there seems to be no way to do it (because a dash normally introduces command options). E.g., the command
dir > -junk
will create such a funny file (like in DOS, the symbol ">" redirects the output from the dir command to a file named "-junk"). Since the regular way of removing the file -junk does not work, I use:
rm ./-junk
The "dot slash" at the beginning means "the current directory" and here serves just the purpose of hiding the leading dash so it is not interpreted as introducing an option to the rm command. The point here is that I would rather stick to traditional naming conventions than face the occasional complications.
Besides using autocompletion, apostrophes and quotes, I can manipulate files with weird names using \ (backslash). Backslash hides the special meaning of the subsequent character. For example, i can create a weird file with the name *?[ using the following command:
touch \*\?\[
(The touch command creates an empty file or, if the file exists, updates its date/time of last modification.)
4.1.2 What are the different directories for?
Linux filesystem tree is large and complicated. It will vastly improve your skills if you familiarize yourself with it.
Briefly, typical Linux contains five filesystems. These filesystems can reside on a single or different physical hard drives and/or hard drive partitions, depending on the size and need of your system. (A single filesystem can also be distributed between different physical devices, if needed.)
The root "/" filesystem contains
