Do Some Basic UNIX
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Some basic unix commands
Want more? Try the excellent tutorials at FreeEngineer.org, Mayo, UnixGeeks.org or Idaho state
Command Meaning man function show the manual page for a function top shows currently running processes - do not leave this running for more than 30sec (ctrl-c) ps show the names of all running processes mkdir dir_name create a sub-directory of the current directory rmdir dir_name remove a directory. You must remove files in the directory first. cp source dest copy a file or directory from source to dest rm file_name remove a file (permanent!) chmod xxx file_name change the file permissions:
Three numbers indicate the permissions for the owner, the group and the world.
- 1 - execute permission
- 2 - write permission
- 4 - read permission
You can add these permissions together, for example:
- 7 - read, write, execute
- 6 - read and write (not execute)
- 5 - read and execute (not write)
chmod 777 filename
- Give all users read, write and execute
chmod 744 filename
- owner read, write, execute
- group members and all others read only
chmod 755 filename
- owner read, write, execute
- all other read and execute (but not write)
chmod 700 filename
- owner read, write execute
- others: no access
chmod -R will make these changes to all of the files in any sub-directories, as well.
ls list contents of current directory ls -l list the contents of the directory (long form, showing sizes) ls dir_name list the contents of the named directory cd dir_name change to the named directory pwd show the name of the current directory . the current directory .. the parent directory of this directory more file_name print out the contents of the named (text) file df show the free space on the present disk du show the disk usage on the system * unix wild card - matches all file names (except those beginning with '.')
e.g. rm * will remove all files from the current directory!
<blink>You will absolutely never type 'rm *'. Ever.</blink>
Always type something like "ls *" first to verify what such a wildcard will match
xemacs file_name
textedit file_name
nedit file_name
vi file_name
These are all text editors that are found commonly on unix systems.
Most people seem to prefer xemacs, but each has its adherents.
?
matches any single character