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--- eg-253:unix4 [2007/09/21 14:55] – eechris
+++ eg-253:unix4 [2011/01/14 12:45] (current) – external edit 127.0.0.1
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+====== UNIX Tutorial Four ======
+===== 4.1 Wildcards =====
+==== The * wildcard ====
+The character ''*'' is called a wildcard, and will match against none
+or more character(s) in a file (or directory) name. For example, in
+your **unixstuff** directory, type
+<cli>ubuntu@ubunbtu:~/unixstuff$ ls list*</cli>
+This will list all files in the current directory starting with **list....**.
+Try typing
+<cli>ubuntu@ubunbtu:~/unixstuff$ ls *list</cli>
+This will list all files in the current directory ending with **....list**.
+==== The ? wildcard ====
+The character ''?'' will match exactly one character.
+So **?ouse** will match files like **house** and **mouse**, but not **grouse**.
+Try typing
+<cli>ubuntu@ubunbtu:~/unixstuff$  ls ?list</cli>
+===== 4.2 Filename conventions =====
+In naming files, characters with special meanings such as **/ * & %**, should be avoided. Also, avoid using spaces within names. The safest way to name a file is to use only alphanumeric characters, that is, letters and numbers, together with **_** (underscore) and **.** (dot).
+^ Good filenames      ^ Bad filenames        ^
+|''project.txt''      | ''project''          |
+|''my_big_program.c'' | ''my big program.c'' |
+|''fred_dave.doc''    | ''fred & dave.doc''  |
+File names conventionally start with a lower-case letter, and may end with a dot followed by a group of letters indicating the contents of the file. For example, all files consisting of C code may be named with the ending **.c**, for example, **prog1.c**. Then in order to list all files containing C code in your home directory, you need only type ls ***.c** in that directory.
+<note warning>**Beware**: some applications give the same name to all the output files they generate.
+For example, some compilers, unless given the appropriate option, produce compiled files named **a.out**. Should you forget to use that option, you are advised to rename the compiled file immediately, otherwise the next such file will overwrite it and it will be lost.</note>
+===== 4.3 Getting Help =====
+==== On-line Manuals ====
+There are on-line manuals which gives information about most commands. The manual pages tell you which options a particular command can take, and how each option modifies the behaviour of the command. Type ''man //command//'' to read the manual page for a particular command.
+For example, to find out more about the ''wc'' (word count) command, type
+<cli>ubuntu@ubuntu:~/unixstuff$ man wc</cli>
+Alternatively
+<cli>ubuntu@ubuntu:~/unixstuff$ whatis wc</cli>
+gives a one-line description of the command, but omits any information about options etc.
+==== Apropos ====
+When you are not sure of the exact name of a command,
+<cli>ubuntu@ubuntu:~/unixstuff$ apropos keyword</cli>
+will give you the commands with keyword in their manual page header. For example, try typing
+<cli>ubuntu@ubuntu:~/unixstuff$ apropos copy</cli>
+===== Summary =====
+^ **Command**            ^ **Meaning**                                       ^
+| ''*''                  |match any number of characters                     |
+| ''?''                  |match one character                                |
+| ''man //command//''    |read the online manual page for a command          |
+| ''whatis //command//'' |brief description of a command                     |
+| ''apropos //keyword//''| match commands with **keyword** in their man pages|
+----
+[[eg-253:unix3|{{eg-253:nav-left.gif|Previous}}]] [[eg-253:unixtut|{{eg-253:nav-home.gif|Home}}]] [[eg-253:unix5|{{eg-253:nav-right.gif|Next}}]]
+ --- //[[C.P.Jobling@Swansea.ac.uk|Dr Chris P. Jobling]] 2007/09/21 16:46//