Emacs & XEmacs Guide

GNU Emacs is a free, portable, self-documenting, customizable, extensible and real-time text editor, Emacs was originally written by Richard Stallman, the founder of the GNU Project, and James Gosling, the creator of the Java language. XEmacs has evolved from the original Emacs, with more GUI and content-based formatting support. For the user-friendly interface reason, I stick to Xemacs all the time.

I found Xemacs was not convenient to use at the beginning, since I was used to the vi and it's shortcuts. However, when I became more experienced I found Xemacs much powerful than vi in most aspects. (X)Emacs is the monster of all editors! It is more than just a text editor. It is a huge and complete system for development, communications, file management, and things you wouldn't even imagine. I only know a very limit features of Xemacs.

Vi (vim) and Emacs (Xemacs) have a very different look and feel, but that's not a real reason for choosing one over the other. Vi is much smaller and loads much faster, while Xemacs is a powerful tool for complex files and software development. They were designed for different jobs, they are better at different things, and I use both of them depending on the job.

Xemacs automatically saves the files you are editing by default. The name of the autosave file is the same as the name of the file you are editing, with a sharp (#) added to the beginning and to the end. When you do a file save, Xemacs creates a backup file of name with a tilde (~) added to the end. When Xemacs starts up, it reads the file ~/.emacs or ~/.xemacs/init.el to customize the Xemacs. You could modify this file by your favorite with Lisp format, e.g. if you like your Xemacs working as a pure txt editor, add the following in the .emacs file:

(setq default-major-mode 'text-mode)
(add-hook 'text-mode-hook 'turn-on-auto-fill)
(setq-default transient-mark-mode t)

There are several basic concepts (environment) of Xemacs: file, buffer, window, frame, echo area (mini-buffer) and mode line. When you are editing a file on disk, Xemacs read a copy of it to initialize a buffer and write a copy of a buffer out to a file to save it; a buffer is the basic editing unit hoding the text you actually edit. You can have multiple buffers but can only edit one buffer at a time; A window is the view of a buffer while frame is the whole screen of Xemacs with all buttons at the top. You could loosely call frames as windows; the echo area is the area at the very bottom of the XEmacs screen and is used to interact with you; the mode line is above the echo area on the XEmacs screen, showing the status and what is happening in the current window.

Some tips about Xemacs:

• without X server, "Xemacs -nw" (no window mode) will open in the terminal, "Ctrl-z" switch back to the shell and type "fg" to go back Xemacs
• command-handling "M-x" or "Alt-x" is not available in some cases, use "Esc x" instead
• using tab or hitting space half will try to complete the command automatically
• "M-x indent-buffer (indent-region)" will indent the buffer (region) contents
• "M-x set-variable RET c-basic-offset RET " can set the indent value
• a simple .emacs file with c/c++ style setting and my simpler .emacs file
• remote access by Ange-ftp & EFS (Emacs File System):
  Ctrl-x d RET /huang@gate.csd.ca:source/mpi.cc RET
  Ctrl-x d RET /gaul.csd.uwo.ca: RET
• remote access by Tramp (Transparent Remote Access, Multiprotocols):
  C-x d RET /[huang@gate.csd.ca]/csd/grad/huang RET
  C-x d RET /[ssh/greatwhite.sharcnet.ca]/ RET

You can do most jobs from the menus of Xemacs. But the more efficient way for editing is using shortcuts. Below are some most commonly used commands or keystrokes:

Mode	Keystroke & command	Description
basic	Ctrl-x Ctrl-f	open a file
	Ctrl-x d	DirEditting mode, identical to Alt-x dired
	Ctrl-x Ctrl-c	quit a file and the Xemacs
	Ctrl-x Ctrl-s	save a file
	Ctrl-x Ctrl-w	write to a new file
	Ctrl-x Ctrl-h	get help
	Ctrl-h f (i, t, k, v)	get help for functions (info, tutorial, key variables, etc..)
	Alt-x speedbar	pop up a speedbar
	Alt-x shell (term)	switch to a shell (terminal)
buffer & window	Ctrl-x Ctrl-b	list buffers
	Ctrl-x o	switch to a buffer
	Ctrl-x k	kill a buffer
	Ctrl-x 3	split the window vertically
	Ctrl-x 2	split the window horizontally
	Ctrl-x 1	make into one window
motion	Ctrl-v	Page down
	Alt-v	Page up
	Ctrl-p (n)	move to Previous (Next) line
	Ctrl-a (e)	move to the start (end) of the line
	Ctrl-f (b)	move Forward (Backward) one character
	Alt-<(>)	move to the beginning (end) of the frame
	Alt-x goto-line	go to certain line
editing	Ctrl-g	abort (quit) current command
	Ctrl-x u	undo
	Ctrl-_	more convenient undo
	Ctrl-Space (Ctrl-@)	set a mark
	Ctrl-x h	select the whole frame
	Ctrl-w	cut the selected area
	Esc w	copy to where the mark ends
	Ctrl-y	yank (paste) back whatever you copied
	Ctrl-d	kill one character
	Ctrl-k	kill to the end of the line
	Ctrl-a Ctrl-k Ctrl-k	kill an entire line
	Ctrl-u 3 Ctrl-k (d)	kill the next three lines (characters)
search & replace	Ctrl-s	search
	Ctrl-r	search backwards
	Esc %	begin a search and replace
	!	replace all occurrences at once
	Space	replace
	n	skip the replace
	Esc	stop the search and replace
	Esc Ctrl-c	continue with the search and replace
mode	Alt-x text-mode	text-mode
	Alt-x c-mode (c++, java, tex...)	programming mode
	Alt-x makefile-mode Enter	makefile mode
	Alt-x overwrite-mode Enter	overwrite mode
	Alt-x font-lock-mode	activate color highlighting
	Alt-x auto-fill-mode	auto wrapping
	Alt-x auto-save-mode	auto save
	Alt-x blink-cursor-mode	blinking cursor

Vi & Vim Guide

Vi is a small, fast and efficient text editor that is installed by default in almost any Unix or Linux system, and Vim (Vi IMproved) is an enhanced version of vi. Most people find vi somewhat hard to learn at first, but it enables fast, simple and effective editing once you get used to it. I got hooked to vi when I first worked with Sun Sparc10 workstation in 1995. Vi is extremely powerful in moving around files without touching any arrow keys. Vi operates in three modes: command mode (colon prompt), insert mode and default mode. For insert mode, press ESC and type colon to switch to command mode. Vi works in default mode after ESC is pressed in all modes (without input colon). In default mode, we are able to move around in the file, switch to insert mode or command mode.

Follow is the vi/vim commands I most use:

Command	Mode	Description
vi filename	default	start editing a file
:wq	command	write to disk and quit ( equal to :x)
:q!	command	quit without saving any changes
:e!	command	recover to the original without any changes
:!command	command	execute a command; :!sh fork a shell, Ctrl-d to exit
h; l; k; j	default	one space to the left, right; one line up, down respectively
^; $	default	the beginning or end of current line
w; e	default	the beginning or end of next word
Ctrl-b; Ctrl-f	default	one page up (backward) or down (forward)
:number	command	move line with the number
Ctrl-L	command	clear and redraw the screen
G	default	move to the end of file
/string; n	default	search string and repeat search (next)
a; A	default	append from next letter or the end of current line
i; I	default	insert from current position or the beginning of current line
o; O	default	open new line down or up of current line
x	default	delete single character; 5x deletes 5 characters
dw; dd	default	delete word or linde; 5dw deletes 5 words and 5dd deletes 5 lines
yy	default	yank (copy) into buffer; 5yy copies 5 lines into buffer
p; P	default	paste buffer to next or previous line
u; U	default	undo last change or restore the current line
:set num; :set nonum	command	turn on or off line numbering
:set ic; set noic	command	ignore (or not ignore) case when searching
ma; :'a; y'a; d'a	default command	set marker 'a' (could be 'a' to 'z') to the current position, go to marker 'a', copy text from current position to marker 'a' into buffer, delete text from current position to marker 'a'
:%g/^#/d; :%s/^#//g	command	delete all comment lines or uncomment all the comment lines
:[10-20]g/hello/d; :[10-20]v/hello/d	command	delete all lines containing (or not containing) text "hello" from line 10 to 20
:i,jd; :'a,'bd	command	delete text from line i to j or from marker 'a' to marker 'b' inclusively
:i,js/old text/new text/g	command	substitute "new text" for "old text" from line i to j
:'a,'bs/old text/new text/g	command	substitute texts from marker 'a' to marker 'b'
:25,30m50; 'a,'bm50; 25,30co50	command	move lines 25-30 to a new position after line 50; move the text between markers to line after 50; copy lines 25-30 to line after 50

Commonly Used Unix/Linux Tools and Commands

Browser	lynx, mozilla, konqueror, nautilus
Email	pine, mutt, kmail, gnus, balsa
Download	(s)ftp, wget, kget, downloader for X
Editor	pico, vi, (x)emacs, ginf(html), kite(latex), kate
Zip	zip, unzip, gzip, zcat, bzip2, tar
PS/PDF	enscript, dvips, ps2pdf, pdf2ps, a2ps, ps2epsi, xpdf, gs, gv, ggv
Image/Graphic	xv, xfig, dia, gimp, gnuplot
Instant messenger	licq, amsn, gaim
Mutimedia	mpg123, xmms, mplayer, toaster
Office suite	abiword, kword, koffice, openoffice
IDE	glade, motor, eclipse

Command	Command line with arguments	Description
a2ps	% a2ps input -R -B --right-footer='%s./%s#' -o output.ps % a2ps -r --columns=1 -B -f10 --border=no -MLetter --pretty-print=plain -o output.ps input	arguments: -r landscape (-R for portrait), one column per page (default is 2), -B no header , -f10 font size, --border=no no border, -MLetter paper size to Letter, --pretty-print=plain print mode turning off the highlights of keywords.
	% a2ps input -2 -B --right-footer='%s./%s#' ---footer='cenfooter' -header='test' --cen='report' -o output.ps	more arguments: $Q = Page $p./$p# (page number for this file), %Q = Page %p./%p# (current page number), %s. (current sheet number), %s# (total number of sheets), $s# (number of sheets of the current file)
	% a2ps $1 --columns=2 --pretty-print=$2 --font-size=8 --header='ID: 12345' -o $3 % a2ps typescript -2 -B --right-footer='%s./%s#' --footer='ID: 12345' --header='Asn 1' --cen='Captured result' -o output.ps % a2ps main.cpp -B -R --columns=1 --right-footer='%s./%s#' --left-footer='ID: 12345' --header='Asn 1' --cen='main.cpp' -o main.ps	different output format
ar	% ar rs liblprint.a lprint1.o lprint2.o lprint3.o	creat a static library with several object files
	% ar -t /usr/lib/libm.a	show the library object dependency of libm.a
	% ar -d liblprint.a lprint3.o % ar -s = ranlib	delete the module
awk	% ls -aRl | awk '{sum = sum + $5} END {print sum}'	sum up and print out the file sizes
bzcat	% bzcat prog-2.0.patch.bz2 | patch -p0	Unzip the bzip2 file and do the patching
cat	% cat file | tr -cd b | wc -m	count the number of "b" in the file
	% cat id.pub | ssh huang@csd.uwo.ca "(mkdir .ssh; cd .ssh; cat>> auth)" % cat file | ssh host "cat >> file"	ssh could be "rsh" or "rlogin"
cb	% cb -s test.cc > test1.cc	indent code according to K&R style (same as indent)
	% cb -j test.cc	put split lines back together
chmod	% chmod -R 755 {zhu,wu,liang}/Asn1/docs/* % chmod -R 755 [a-k]*/Asn2/*	change the dir/subdir's permission
col	% man find | col -b > find.txt	output a man page into a plain text file
crypt	% crypt key < plaintext > encrypted % crypt key < encrypted > plaintext	Unix command, Linux's crypt(encrypt) is a function call
diff	% diff -Nur prog-1.0 prog-2.0 > prog-2.0.patch % patch -p0 < prog-2.0.patch	Make a patch
dig	% dig @ns1.uwo.ca genome1.beowulf.uwo.ca % dig -x 129.100.171.47	nslookup
find	% find / -name abc -print > result 2> errout % find / -name abc -print 2>&1 1> logfile	B shell
	% (find / -name abc -print > result) >& errout % find / -name abc -print >& logfile	C shell
	% find / -type f \( -perm -2 -o -perm -20 \) -exec ls -lg {} \; > files-results % find / -type d \( -perm u=rwx,g=rx,o=rx \) -exec ls -ldg {} \; >dir-results	find the files or directories with specific permission
	% find [v-z]*/A*3/ -user wang -exec rm -f {} \;	delete all files created by user "wang" in the directory between "v*" to "z*", subdir of Asn3
	% find $HOME \( -name a.out -o -name '*.o' \) -atime +7 -ok rm {} \;	remove all files named a.out or *.o that have not been accessed for a week, need to confirm for each execution
	% find . \( -type f -a -size -10k \) -ok exec cp {} ~/tmp/ \;	copy small size regular files to a directory
	% for i in `find / -name *.[ch]`; do grep -H jiffy $i; done	find all files with defined string. -H prints the filename for each match
finger	% finger @hostname	show users' info ( some versions need a "*" before "@")
	% finger -f | awk '{print $1} % finger -q -f | awk '{print "User", $1, "is logged in on TTY:", $2}'	print out the login users with desired format
gcc	% gcc -o math math.c -lm	link the shared libary (libm.so)
	% gcc -o math math.c -lm --static	static link. all code of libm.a is merged into your distributed executable
	% gcc -E test.c > test.i	turn off compilation phase and display the preprocess info
	% gcc -DBUFFERSIZE=1024 -D"max(A,B)=((A)>(B)?(A):(B))" test.c	define the constant and macro
grep	% grep -r string rc.d/	find string in all files in rc.d dir/subdir recursively, the same as "-d"
	% grep -i '^\(.\).*\1$' file	all lines whose first letter is the same as the last one regardless of the case (-i =-y)
gunzip	% gunzip [-q] < file.tar.gz | tar xvf -	the same as Linux's "tar zxvf file.tar.gz"
indent	% indent -bad/-st/-kr/ test.c > newformat.c	beautify the code with different format as cb does
kill	% kill -9 -1	Kill all processes in the login machine
ls	% ls -aul	access tme
lsof	% lsof | nl % lsof -u huang	list all open files (by specified user)
	% lsof -i -nP | grep ssh % lsof -i :5000 % lsof -i :smtp % lsof -i @hotmail.com	List all open files associated with Internet connections
	% lsof /dev/cdrom % lsof +D /tmp % lsof `which sendmail` % lsof -t `which sendmail`	Who are using these files?
netstat	% netstat -rn	routing table
	% netstat -alp	connection statistics
nl	% nl -ba message.log | tail -30 | grep error	print the message having error in the last 30 lines of the log file
nm	% nm -a prog % nm -s prog	list all the symbols of the object file
	% nm -o /lib/* /usr/lib/* /usr/lib/*/* /usr/local/lib/* 2>/dev/null | grep 'atoll'	search the libraries for the function
	% nm -ng prog	show external symbols and sorted by addresses
nohup	% nohup find / -name abc -print > result 2>/dev/null &	continue finding after logout
ps	% ps -efww	full format (Linux)
	% /usr/bin/ps -axf	pstree plus ps (Linux)
rcp	% rcp brown:hb/\* .	the same as "scp brown:hb/* .". rcp needs .rhosts in remote hosts: snm.szptt.net.cn huang java huang
rusers	% rusers -l hostname	show all users in the host
	% rusers -a	show all host names in the network
sed	% cat file | sed 's/^#/;/g' > newfile	change comments format (shell to lisp)
	% ls *htm | sed 's/\(.*\)htm/mv & \1html/' | sh	change the extension
	% sed -e 's/\(\<[A-Za-z]*[aeiou][A-Za-z]*[aeiou][A-Za-z]*\>\)/(\1)/g' file	surround all words containing 2+ or vowels with (), "tea"-->"(tea)" (<> match words)
sh	% sh -xv shell_script	debug the bsh script program (csh: % csh -xv)
tar	% tar tvf file.tar	show all the files in a tar file
	% tar rvf my.tar newdir	append files in newdir to my.tar
	% tar uvf my.tar mydir	update my.tar with newly updated files in mydir
	% tar cvf - file | gzip > file.tar.gz	the same as linux's "tar cvfz file.tar.gz file"
	% (cd ~huang/target; tar -xvf - .) | (cd ~huang/backup; tar -xvf -) % (cd ~/target; tar cf - .) | rsh casky "cd ~/backup; tar xf -"	backup the files in remote machine
tr	% tr -d "\015" < input > ouput	remove the ugly ending char in text files ftped from windows to Unix, the same as "dos2unix"
	% cat a.txt | cat abc | tr '[a-zA-Z]' '[n-za-mN-ZA-M]' > encrypted.txt % cat a-encrypted.txt | tr '[a-zA-Z]' '[n-za-mN-ZA-M]' > decrypted.txt	the easiest way of encryption
uuencode	% uuencode a.out key > secret.out % uudecode secret.out	"key" is a decode label
wget	% wget -r -l 4 -np -N http://www.abc.com % wget -c -L -nH http://www.abc.com/big.zip % wget --passive-ftp ftp://abc.com/d*/*.doc	download the contents of the website, recursively (-r) with depth 4 (-l 4), page requisite mode (-p), not ascend the parent directory (-np), enable timestamp (-N), continue download the interrupted file (-c), only get files from relative links (-L), disable long header (-nH).
	% wget -E -k -K -p http://www.abc.com % wget -r -H -l inf --ignore-length -p -e robots=off http://www.abc.com % wget --http-user=huang --http-passwd=abc --cache=off --cookies=off http://www/secret	html-extension mode (-E) is useful for asp and cgi pages, link-convert (-k) and backup the original version (-K, affects -N), enable span-host (-H), ignore the bogus "Content-Length" headers by CGIs (--ignore-length), turn off the robots mechanism(-e )
	% wget --save-cookies cookies.txt --post-data 'user=foo&password=*' http://www.abc.com/auth.php % wget --load-cookies cookies.txt -p http://www.abc.com/doc/article.php	llogin to the server and save the cookie file ( done only once), then grab the desired pages
who	%who -u | sort +0 -1 -u	display the login users without repeat names
	%who -u | cut -c1-10 | sort | uniq -c | grep -v " 1 "	display the users having more than on terminals
xterm	% xterm +ls -sb -rightbar -sl 1000 -j -title "dreamer" -fn "*-courier-bold-r-*-140-*" -b 5 -display 0:0 -bg black -fg green -geometry 80x50+10+5 &	open an xterm with pure subshell (+ls) mode, scrollbar (-sb) with 1000 lines (-sl) in the right side (-rightbar), jump scrolling (-j), font defined (-fn), black background (-bg) and green foreground (-fg), 80 characters per line, 50 lines, ordinate (10, 5) from upper-left corner. ( -10-5 means x ordinate of 10 from the right, y ordinate of 5 from the bottom)

A Java Utility for IBM Crosspad Devices

I've been doing some research on digital inks. IBM's CrossPad was one of the devices we used to collect people's writing. But there's no out of box tool to view and manipulate the collected writing.

So I wrote a Java GUI application for such purpose. It would be handy if you are also working on the same area. The source code can be downloaded here.
Screen-shot:

Unix/Linux Shell Scripts

Shell scripts are very powerful to solve some problems in Unix systems. Among bsh, csh and ksh, Bourne shell is the most commonly used one in the system job handling.

A brief summary of test operators in shell programming:
[ -d name ] true if name is a directory and exists
[ -f name ] true if name is a file and exists
[ -s name ] true if name is an existing, not empty file
[ -r name ] true if name is a readable file (read access)
[ -w name ] true if name is a writeable file (write access)
[ -x name ] true if name is an executable file (execute access)
[ -z name ] true if name has zero length
[ -n name ] true if name has non zero length
[ string ] true if string is not empty
[ name1 = name2 ] true if string name1 and name2 are equal
[ name1 != name2 ] opposite of =
[-d dir1 -a -f prog] -a: "and" (logical "and") -o: " or " (logical "or")
[ ! -f name ] true, if file name does not exist
[ num1 -eq num2 ] true if number num1 and num2 are equal
[ num1 -neq num2 ] true if number num1 and num2 are not equal
[ num1 -lt num2 ] true if number num1 is less than number num2
[ num1 -gt num2 ] true if number num1 is greater than number num2
[ num1 -ge num2 ] true if number num1 is greater than or equal to num2
[ num1 -le num2 ] true if number num1 is less than or equal to num2

Following are some examples:

1. Check your system's info and print the shells available in your system:

#!/bin/sh
# check your system's info and which shells are available
echo "The machine information: `uname -s` version `uname -r`"
for x in sh bsh bash csh tcsh ksh zsh; do
test -x /bin/$x && shells="$shells $x"
done
echo "The following shells are available in the system: $shells"

2. Check whether the input names are executable files from your searching path:

#!/bin/sh
# check whether the input names are executable files from your searching path
# if so, print the whole path of them 
mypath=`echo $PATH | tr ':' ' ' `

for filename in $*; do
for apath in $mypath ;do
if [ -x $apath/$filename ]; then
  echo $apath/$filename
fi
done
done | while read finded; do
ls -l $finded
done

3. Print shell command arguments in reverse order:

#!/bin/sh
# Print all the arguments reversely 

inputString=""
for i in $*
do
inputString="$i $inputString"
done
echo "The reverse arguements you typed are:"
echo $inputString
exit

4. Menu switch:

#!/bin/sh
# interpret the input 

echo "Enter a command (list/user/disk/quit/Quit):"
while read cmd
do
case "$cmd" in
list) ls -al ;;
user) who -l ;;
disk) df . ;;
quit|Quit) break ;;
*) echo "$cmd: No such command" ;;
esac
done
echo "All done"

5. Calculate the factorial of a number n!=n*(n-1)!

#!/bin/sh
#calculate the factorial of a number n!=n*(n-1)!

if [ $# -eq 0 ]; then
echo " Usage: factor.sh number"
exit 1
elif [ $# -gt 1 ]; then
echo " Too many arguments"
exit 1
fi

COUNT=0
VALUE=1
while [ $COUNT -lt $1 ]; do
COUNT=`expr $COUNT + 1`
VALUE=`expr $VALUE \* $COUNT`
done

#display the results
echo "The factorial of $1 is $VALUE"

6. Check whether the input words are existing in a given file:

#!/bin/sh
#check if the input are valid words in a specified dictionary
if [ $# -lt 2 ]; then
echo " Usage: check-word.sh dictionary-file word1 word2 ..."
exit 1
fi

COUNT=1
TARGET=$1
shift
for WORD in $*; do
echo -n "$COUNT : "
COUNT=`expr $COUNT + 1`
echo -n "Word $WORD "
CHECK=`eval "grep -w $WORD $TARGET | wc -l"`
if [ $CHECK -eq 0 ]; then
echo "is not found in $TARGET !"
else
echo "is found in $TARGET !"
fi
done

7. Check whether the input names are executable files from your searching path:

#!/bin/sh
# check whether the input names are executable files from your searching path
# if so, print the whole path of them 

mypath=`echo $PATH | tr ':' ' ' `

for filename in $*; do
for apath in $mypath ;do
if [ -x $apath/$filename ]; then
    echo $apath/$filename
fi
done
done | while read finded; do
ls -l $finded
done

8. Check mail status and display mail headers for new and unread mails:

#!/bin/csh
# check mail status and display mail headers for new and unread mail

set maildir="/var/mail"

if (-e $maildir/$USER.lock == 0) then
if ((-e $maildir/$USER != 0) && (-z $maildir/$USER == 0)) then
mailx -H | awk 'BEGIN { c = 0 } { if (($1 ~ /N/) || ($1 ~ /U/)) {print $0; c = 1} } \
             END { if (c == 0) print "no new mail" }'
else
echo ' No mail for '$USER
endif
else
echo ' Your mailbox is locked'
endif

9. Change files' permission in directories and their subdirectories:

#!/bin/sh
# Change the permissions of all files in directories including subtree.
# Use command "find" to print all files(directories) in a path or paths.
# Pipe each file(directory) name to input function "read".  
# Then use the script of  question1 to change the permission.
# Select one or more directories to change. 
# Function current path if without argument.  

if [ $1 = ? ] || [ ! -d $1 ]
then echo " Usage: ch-perm.sh [path1] [path2] ... "
exit
fi

# If no argument then set path to current directork
path=${*:-.}

find $path -depth -print | while read file
do
if [ -d $file ]; then
chmod 711 $file
elif [ -x $file ]; then
chmod 755 $file
else chmod 644 $file
fi
done

echo " Job was done successfully!"
exit

10. A recursive version to do the above task:

#!/bin/sh
# set the permissions: directories 711, excutable files 755, else 644.
# [ -n "not_empty_string"]; [ -e "exist_file" ]; 
# [ -f "regular_file" ]; [ -L "symbol_link" ]

dir=`pwd`
command=$0
echo "Directory: $dir   Command: $command"

for file in *
do
if [ -d $file ]
then
    echo "directory: $file "
    chmod 711 $file
    cd $file
    $dir/$command
    echo "now directory is : `pwd` "
    cd ..
elif [ -x $file ]
then
    echo "excutable file: $file "
     chmod 755 $file
else
     echo "regular file: $file "
     chmod 644 $file
fi
done

echo " Job was done successfully!"
exit