Hi
Thanks, got it.
So, instead of using let and still have the same effect, I can use expr right?
Let command is just simpler since I do not need to use expr command and worry about the backquotes, spaces on either side of + sign and so on so forth
Right?
The let command is unnecessary and is not standard.
There is no need for expr in a modern (i.e., POSIX) shell. Use the shell's own arithmetic capabilities:
Hi,
I have a statement in shell script which i am writing below:
if ]
then
.....
What is the meaning of -a option in files, meaning of the statement in the if condition ] means.
Thanks (3 Replies)
can someone please tell me what is wrong with the below. i'm trying to get a script to run if the content of a variable is either small letter y or capital letter Y.
if
then
whatever
fi (4 Replies)
I want to write a program that would convert yard to feet and feet to yard.
i.e
1 yard = 3 * feet
Echo "enter a"
read a
expr a *3
The trick is that I want to give the user some options. After the conversion from yard to feet is done, I want to ask the user whether or not he/she wants to... (10 Replies)
In my ksh script, if the conditions of a if statement are true, then do nothing; otherwise, execute some commands.
How do I write the "do nothing" statement in the following example?
Example:
if (( "$x"="1" && "$y"="a" && "$z"="happy" ))
then
do nothing
else
command
command
fi... (3 Replies)
Hi All,
I am using Unix ksh script.
I need to insert values to a table using the o/p from a slelect statement.
Can anybody Help!
My script looks like tihs.
---`sqlplus -s username/password@SID << EOF
set heading off
set feedback off
set pages 0
insert into ${TB_NAME}_D... (2 Replies)
I have the program:
#!/bin/ksh
echo Please enter yes or no
read n
typeset -l n
if ]
then
echo My name
exit
else
echo delete my name
fi
Question:
How can I make the program accept only the word "yes" or "no" otherwise it will ask the user to re-enter?
Thanks! (7 Replies)
I'm trying to create a script that would allow me to identify the sucessful removal of a file. Here's what i put together so far, let me know if it's correct or not.
FILE_NAME="cactus.dat"
FILE_FIND='find / -name $FILE_NAME'
if ;then
echo "cactus.dat was not removed successfully" ... (3 Replies)
Hi,
I have this code here. Its suppose to do something when certain condition is met, I'm pretty sure at least one of the condition will be meet somewhere in the loop but it always go to else part of the script.
Is something wrong on this script?
age_list=`tar -tvf /home/dir/$tarfile... (4 Replies)
Hi folks,
I have a scenario to convert the update statements into insert statements using shell script (awk, sed...) or in database using regex.
I have a bunch of update statements with all columns in a file which I need to convert into insert statements.
UPDATE TABLE_A SET COL1=1 WHERE... (0 Replies)
Discussion started by: dev123
0 Replies
LEARN ABOUT BSD
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 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.
7th Edition April 29, 1985 EXPR(1)