10-31-2006
Hi,
Thank you for your reply. Well, the metacharacter '!' is used to refer to the history of the commands.
So, for example, if you did ls -a, then followed it by rm *, then did echo $PATH, then !l (!-el) would be the same as the last command beginniing with "el" i.e. ls -a, !r would be rm * and !e would be echo $PATH.
I just don't know why echo "!l" is interpreting !l as a shell command!!! Surely it shouldn't when I double quote it.
Yes, escaping it with a backslash DOES work (i.e. "\!l" does work), but I don't see why we have to backquote ! when it is already is double quote! After all, we can do echo "ls *", and don't have to do echo "ls \*".
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
Is there a way to use metacharacters in a loop or in an if.
I want to allow a user to enter Y, y, Yes, yes, Yah, etc...
in a loop I tried:
read response
while *" ]
do........
and
while *" ]
do .........
this works for grep or egrep but not in loops
Why?????? (4 Replies)
Discussion started by: jrdnoland1
4 Replies
2. UNIX for Dummies Questions & Answers
I want to display an asterisk to the screen as part of a string. I know how to use the Backslash to escape it's value. But how do I display it without showing the Backslash? (1 Reply)
Discussion started by: regencyabs
1 Replies
3. Shell Programming and Scripting
I have an extraordinary problem with a csh script.....(feel free to berate the use of this but I'm modifying an existing bunch of them)
Anyway, I have a master csh script which in turn calls a second csh script. This second csh script is below. Within this second script are two compiled C++... (1 Reply)
Discussion started by: pollsizer
1 Replies
4. Shell Programming and Scripting
:confused:Hi ,
Can someone please advise what is the meaning of metacharacters in below code?
a_PROCESS=${0##*/}
a_DPFX=${a_PROCESS%.*}
a_LPFX="a_DPFX : $$ : "
a_UPFX="Usage: $a_PROCESS"
Regards,
gehlnar (3 Replies)
Discussion started by: gehlnar
3 Replies
5. Shell Programming and Scripting
I'm trying to create a bash script that takes a URL as one of its arguments like this:
./script.sh http://url.cfm?asdf&asdf=234
variable=$1
echo $variable
I'm having trouble storing the URL because it contains the meta character "&" which is being interpreted... thus when I run the... (4 Replies)
Discussion started by: kds1398
4 Replies
6. Shell Programming and Scripting
If I have a filename as
filename.txt.20090807
and I use
for FILE in `find . -name "filename*" -type f`
do
my_time=${FILE#./filename.txt.}
I get my output as 20090807
However if my filename is
filename.Y20090807.txt
Is there a way I can use metacharacters in my... (3 Replies)
Discussion started by: RubinPat
3 Replies
7. UNIX for Dummies Questions & Answers
Hello. I am learning how to use Unix through an online course. Unfortunately the text that we use isn't very good, so I could use some help with a pretty basic question.
Use metacharacters and the ll command to list all filenames under the datafiles directory that contain a dot "." with the... (2 Replies)
Discussion started by: feverdream
2 Replies
8. Shell Programming and Scripting
I have prepared a script to submit a string in a txt file.
However there are somethings that I have to check before submitting the string in the txt file.
One of those checks is to determine whether the string entered contains any metacharacters.
I have tried sth like;
echo "string" | grep -v ... (3 Replies)
Discussion started by: ozum
3 Replies
9. UNIX for Dummies Questions & Answers
1) I want to display all the files in a directory that start with the word chapter, are followed by a digit 1,2,6,8, or 9 and end with .eps or .prn
so I came up with this
file ~/temp/chapter.eps ~/temp/chapter.prn
but is there a better way, i.e. combining both file types into the command?
... (2 Replies)
Discussion started by: dunsta
2 Replies
10. Shell Programming and Scripting
I am currently reading a very old reference from O'Reilly: Sed and Awk 2nd Edition reprinted in 2000. So far, it's a solid read and still very relevant. I'd highly recommend this to anyone.
The only problem I have with this book is that I had to resort to bourne shell to get my examples to work... (3 Replies)
Discussion started by: ConcealedKnight
3 Replies
LEARN ABOUT X11R4
suspend
suspend(1) User Commands suspend(1)
NAME
suspend - shell built-in function to halt the current shell
SYNOPSIS
sh
suspend
csh
suspend
ksh
suspend
DESCRIPTION
sh
Stops the execution of the current shell (but not if it is the login shell).
csh
Stop the shell in its tracks, much as if it had been sent a stop signal with ^Z. This is most often used to stop shells started by su.
ksh
Stops the execution of the current shell (but not if it is the login shell).
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
csh(1), kill(1), ksh(1), sh(1), su(1M), attributes(5)
SunOS 5.10 15 Apr 1994 suspend(1)