I generally refuse to use csh and its derivatives for reasons already mentioned in this thread... But, I think you want to change:
to something like:
and I think you want to add something like:
before the code you showed us. I have not tested any of these suggestions, but they should get you a little bit closer to what you're trying to do.
If you want to learn about UNIX and Linux (and BSD) system shell programming, I strongly suggest you get a different book that describes ksh, bash, or some other shell that is based on Bourne shell syntax.
Good luck.
This User Gave Thanks to Don Cragun For This Post:
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)
Hi everyone,
I have never wrote script in csh before, but I need to add only few lines to an existing one. I tried to use the bash standard syntax, and it did not work. So, I attempted to use csh syntax, and it is not working. Can someone help please:
switch ( $Return_Code )
case 0:... (3 Replies)
Ok I asked something similar earlier with no response, so maybe I didn't word it correctly. I'm new at this, so thank you for your help.
Here's what I have right now.
----------------------------
> cat MySourceFile
#!/bin/csh
echo "Please Enter Value For My_Env_Var:"
set answer = $<
... (1 Reply)
I'm having some trouble implementing a basic calculator using command line options. The script is supposed to take (multiple) arguments -a,-d,-m,-s for addition, multiplication, division, and subtraction. I'm pretty sure I know how to parse through the options with getopt(), but I have no idea... (17 Replies)
Hey I am brand new to this forum and scripting.
I have several documents (1000+) all formated exactly the same. Each document contains 97 lines. I want to pull 3 lines from the documents to populate a file. These 3 lines are line number 9, 24, and 58.
Ok my questions: Instead of using... (3 Replies)
Hey all,
I've only just started using UNIX coding on my Masters project, so am still learning!! The script I've been writing is literally just for me to get used to writing it and seeing what I can do with some data I've been given.
I'm trying to write a script, where the penultimate line... (2 Replies)
so just spit ballin here,
i was wondering if anybody knew how to make a chmod calculator script.
basically go to this website http://mistupid.com/internet/chmod.htm
i would like something like this that i can use in a terminal tho. so like i run the scrip and it ask for owner what... (1 Reply)
Hello, I'm in need with a little help for my script please this is the brief i need to complete which I haven't been able to do:
On option 7 stop the calculator
The calculator will keep running until option 7 is chosen. Any other option than 1-7 will generate an error message.
Pls any help... (1 Reply)
Hello, I have to make a calculator in shell script. But I get this error. Can someone help me please?
c.sh: 3: c.sh: i: not found
That's my code.
==========================================================================
#Calculator
i = "yes"
while
do
echo What operation... (2 Replies)
Discussion started by: KJN
2 Replies
LEARN ABOUT V7
expr
EXPR(1) General Commands Manual EXPR(1)NAME
expr - evaluate arguments as an expression
SYNOPSIS
expr arg ...
DESCRIPTION
The arguments are taken as an expression. After evaluation, the result is written on the standard output. Each token of the expression is
a separate argument.
The operators and keywords are listed below. The list is in order of increasing precedence, with equal precedence operators grouped.
expr | expr
yields the first expr if it is neither null nor `0', otherwise yields the second expr.
expr & expr
yields the first expr if neither expr is null or `0', otherwise yields `0'.
expr relop expr
where relop is one of < <= = != >= >, yields `1' if the indicated comparison is true, `0' if false. The comparison is numeric if
both expr are integers, otherwise lexicographic.
expr + expr
expr - expr
addition or subtraction of the arguments.
expr * expr
expr / expr
expr % expr
multiplication, division, or remainder of the arguments.
expr : expr
The matching operator compares the string first argument with the regular expression second argument; regular expression syntax is
the same as that of ed(1). The (...) pattern symbols can be used to select a portion of the first argument. Otherwise, the
matching operator yields the number of characters matched (`0' on failure).
( expr )
parentheses for grouping.
Examples:
To add 1 to the Shell variable a:
a=`expr $a + 1`
To find the filename part (least significant part) of the pathname stored in variable a, which may or may not contain `/':
expr $a : '.*/(.*)' '|' $a
Note the quoted Shell metacharacters.
SEE ALSO ed(1), sh(1), test(1)DIAGNOSTICS
Expr returns the following exit codes:
0 if the expression is neither null nor `0',
1 if the expression is null or `0',
2 for invalid expressions.
EXPR(1)