02-13-2009
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
Hello,
I have a question, please (I am using tcsh).
I thought that if you enclose something in double quotes, then the shell won't interpret it. For example, when I do:
% echo "ls *"
I get
ls *
However, if I do:
% echo "!l"
I get
echo "ls -F"
ls -F (3 Replies)
Discussion started by: A1977
3 Replies
4. 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 $variable
I'm having trouble storing the URL because it contains the meta character "&" which is being interpreted... thus when I run the... (4 Replies)
Discussion started by: kds1398
4 Replies
5. Shell Programming and Scripting
If I have a filename as
filename.txt.20090807
and I use
for FILE in `find . -name "filename*" -type f`
do
my_time=${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
6. 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
7. Shell Programming and Scripting
Hi, all.
I have a need to take a flat file FTP'd from Windows to Unix and convert it for loading into a MySQL database without manual intervention. However, some characters are "fancified" (e.g. the fancy Beginning and End double-quotes from Windows) that show up as codes using vi. I need to... (4 Replies)
Discussion started by: superdelic
4 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 MOJAVE
getopt
GETOPT(1) BSD General Commands Manual GETOPT(1)
NAME
getopt -- parse command options
SYNOPSIS
args=`getopt optstring $*` ; errcode=$?; set -- $args
DESCRIPTION
The getopt utility is used to break up options in command lines for easy parsing by shell procedures, and to check for legal options.
Optstring is a string of recognized option letters (see getopt(3)); if a letter is followed by a colon, the option is expected to have an
argument which may or may not be separated from it by white space. The special option '--' is used to delimit the end of the options. The
getopt utility will place '--' in the arguments at the end of the options, or recognize it if used explicitly. The shell arguments ($1 $2
...) are reset so that each option is preceded by a '-' and in its own shell argument; each option argument is also in its own shell argu-
ment.
EXAMPLES
The following code fragment shows how one might process the arguments for a command that can take the options -a and -b, and the option -o,
which requires an argument.
args=`getopt abo: $*`
# you should not use `getopt abo: "$@"` since that would parse
# the arguments differently from what the set command below does.
if [ $? != 0 ]
then
echo 'Usage: ...'
exit 2
fi
set -- $args
# You cannot use the set command with a backquoted getopt directly,
# since the exit code from getopt would be shadowed by those of set,
# which is zero by definition.
for i
do
case "$i"
in
-a|-b)
echo flag $i set; sflags="${i#-}$sflags";
shift;;
-o)
echo oarg is "'"$2"'"; oarg="$2"; shift;
shift;;
--)
shift; break;;
esac
done
echo single-char flags: "'"$sflags"'"
echo oarg is "'"$oarg"'"
This code will accept any of the following as equivalent:
cmd -aoarg file file
cmd -a -o arg file file
cmd -oarg -a file file
cmd -a -oarg -- file file
SEE ALSO
sh(1), getopt(3)
DIAGNOSTICS
The getopt utility prints an error message on the standard error output and exits with status > 0 when it encounters an option letter not
included in optstring.
HISTORY
Written by Henry Spencer, working from a Bell Labs manual page. Behavior believed identical to the Bell version. Example changed in FreeBSD
version 3.2 and 4.0.
BUGS
Whatever getopt(3) has.
Arguments containing white space or embedded shell metacharacters generally will not survive intact; this looks easy to fix but isn't. Peo-
ple trying to fix getopt or the example in this manpage should check the history of this file in FreeBSD.
The error message for an invalid option is identified as coming from getopt rather than from the shell procedure containing the invocation of
getopt; this again is hard to fix.
The precise best way to use the set command to set the arguments without disrupting the value(s) of shell options varies from one shell ver-
sion to another.
Each shellscript has to carry complex code to parse arguments halfway correcty (like the example presented here). A better getopt-like tool
would move much of the complexity into the tool and keep the client shell scripts simpler.
BSD
April 3, 1999 BSD