Don't use the backticks any more, this is outdated style and not necessary in the Korn shell. If you want to execute a command, then put the output of that command into a variable instead of
use
Second, instead of "expr" or "let" you should use the "(( .. ))" construct, which is easier to read and encouraged by David Korn. Instead of
better write:
Yes, I already know i can be a PITA, no neeed to point that out. ;-))
/switches ranting mode off, reverting back to a humble person
I am trying to install GCC-3.1.1 on an SGI Indigo2. I already have MIPSpro 7.2.1 installed. However, when I try to configure GCC-3.1.1, I get the message "cc ERROR: cc -o conftest -g failed, You must set the environment variable CC to a working compiler."
What is the name of the MIPSpro c++... (1 Reply)
I am trying to install GCC-3.1.1 on an SGI Indigo2. I already have MIPSpro 7.2.1 installed. However, when I try to configure GCC-3.1.1, I get the message "cc ERROR: cc -o conftest -g failed, You must set the environment variable CC to a working compiler."
What is the name of the MIPSpro c++... (1 Reply)
I want to set a variable to be any number of dashes. Rather than doing the following:
MYVAR="------------------"
I'd like to be able to set the variable to, say, 80 dashes but don't want to have to count 80 dashes. Is there a way to do this? (2 Replies)
I need some syntax help (working in a bash shell)
I have a variable which is a filename with an extension, and I need to create another variable with the same name but a different extension
To explain, the input file should be called something like "filename.L1" and the output file should be... (1 Reply)
How do you set a varible with information that contains a string and also another variable? For example:
subject="Attention: $name / This $type needs your attention"
The $xxxx are of course other variables that I instantiated earlier. Is it like Java where you have to use double quotes and... (1 Reply)
In my script, I have the following command....
du -sk `ls -ltd sales12|awk '{print $11}'`|awk '{print $1}'
it returns the value
383283
I want to modify my script to capture that value into a variable. So, I try doing the following...
var1=`du -sk `ls -ltd sales12|awk '{print... (5 Replies)
I am working within a while loop and i am trying to set a variable that will read out each count of the files. the problem is the count variable i have set up gives me a total and not the individual count of each file. in the data area there is 4 abc.dat and 1 def.dat.
how can i do this???
... (2 Replies)
Hi,
I already have one CPP program which invokes the C program.And the C program contains whole function definitions..!This is a working program..I have to enable the logs in both CPP as well as in the C program ..!So I am reading the enviornmental variable log path from the CPP and doing the... (2 Replies)
Hi,
i have a variable which i would like to set inside an if block
for example
IS_VAR=0
if
then
IS_VAR=1
fi
echo IS_VAR
the last echo statement gives 0.So setting variables in the if block doesnt have effect outside the block?Is there any workaround for this?
Thanks ,
Padmini (11 Replies)
Hi ,
Whenever i want to start tomcat server I need to go to <tomcatdir>\bin
and execute startup.sh file.
How would i make this happen whenever i start my machine?
Also want to know How would i set the variable at startup.
for example
I want to set JAVA_HOME and JRE_HOME whenever the... (3 Replies)
Discussion started by: pinga123
3 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)