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_______________________________ Unix __________________________________
You need to know about a dozen commands to function in any operating
system. Unix commands are short and mnemonic and very natural.
Most of them take various -flags to modify their action. You can use
alias newname "something" to name "something" to "newname".
e.g. alias dir 'ls -lF'
All aliases and customizations may be placed in your .tcshrc file.
command -h shows the usage (syntax)
man command will tell you more than you want to know!
Here is a list of the essential commands [and useful aliases]:
ls = list [ alias l 'ls -FC' ], [ alias dir 'ls -lF \!* | more' ]
cp = copy [ alias cp 'cp -ip' ]
mv = move, rename [ alias ren 'mv -i' ]
cd = change dir
rm = remove (delete) [alias rm '/bin/rm -ir'],[ alias del /bin/rm ]
lpr = print file
vi = visual editor (the standard Unix editor, see below)
more = display a file page-by-page
mkdir = make dir
rmdir = remove dir
man = manual (help) on a command
chmod = change mode of file (set permissions)
logout = log off the machine
ssh = log on to another machine (secure shell)
scp = (secure cp) copy files between machines
~ refers to the home dir, . to current dir, .. to parent dir
There are hundreds of other commands/tools, do: xman to see them.
_______________________________ vi editor______________________________
vi filename starts vi on the file, you'll be in command mode
ZZ write (save) and exit :q! quit (exit) without saving
h, j, k, l move cursor left, down, up, right
H to top of page L to bottom of page
^F page forward ^B page backward
1G to top of file G to bottom of file
i insert ...ESC a append (after cursor) ...ESC
o open new line ...ESC O open new line above cursor...ESC
x delete character dw delete word dd delete line
There are many,many more commands and customizations, but these are the
most essential. Current free incarnation is VIM, for linux, Win,...
Best compress/archive utility. zip -h , unzip -h show the options.
I use the following aliases:
alias zp 'zip -oyz' #preserve date,skip links,ask for comment
alias zpm 'zip -oyz9m' # also -m: delete zipped files
alias zpmr 'zip -oyz9mr' # also -r: recurse into subdir's
alias zz 'unzip -l' # list zipped files
alias uz unzip
_______________________________ X Windows _____________________________
Each window is an xterm, emulating a terminal. A window manager (such
as gnome) manages all the windows and the mouse. Can be customized.
The greatest thing about X is that you can run on a remote machine and
display its output on your screen, immensely useful !!!
______________________________ Fortran / C ____________________________
gfortran code.f :compile Fortran code.f and produce executable a.out
gcc code.c :compile C code.c and produce executable a.out
______________________________ Run a code ____________________________
The standard input/output device is the screen, unless redirected, e.g.
a.out will read and write to the screen, but
a.out < dat will read from "dat" and write to screen
a.out < dat > out will read from "dat" and write to "out".
______________________________ Plotting _____________________________
Simplest, nicest (and free) plotting tool ever is: gnuplot
Start gnuplot with: gnuplot, then do: help plot , help set
Everything is on line, nothing to remember !!! Try this:
gnuplot> plot [-4:4] sin(pi*x), cos(pi*x/2) with points
You can get a Windows version for your PC from
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