Hello guys!
Can say me anybody about operatios with unix, I don't to make operations, only inside in a variable, like this
#y=4
#x=2
#let z=$y-$x
#echo $z
# 2
but I can't to make mathematical operations with decimal like this
#y=3.2
#x=1.5
#let z=$y-$x
#echo $z
# 3
this... (2 Replies)
I've been able to generate output based on the code scarfake provided me (thanks again man).
A little background so everyone more or less knows whats going on:
I needed code that would propagate a database with 100,000 entries, for capacity testing purposes, something like a stress test.
... (5 Replies)
Hello all!
I used to use expr for doing simple mathematics, but has a main advantage and a main disadvantage:
The advantage is that it can take variables for numbers
(e.g.{1}: echo "Give me first"
read lol
echo "Give other"
read lil
sum=`expr $lol + $lil`
echo "The sum of $lol and $lil =... (5 Replies)
i want use ssh on the host01 to execute autoexec.sh on the host02 like following :
host01> ssh host02 autoexec.sh
autoexec.sh include nohup command like follwing :
nohup /home/jack/deletedata.sh &
after i execute ssh host02 autoexec.sh one the host01. i can't found deletedata.sh... (1 Reply)
I have a shell script (.sh) and I want to pass a parameter value to the awk command but I am getting exception, please assist.
diff=$1$2.diff
id=$2 new=new_$diff
echo "My id is $1"
echo "I want to sync for user account $id"
##awk command I am using is as below
cat $diff | awk... (2 Replies)
Dear Unix gurus,
We have a config shell script file which has 30 variables which needs to be passed to master unix shell script that invokes oracle database sessions. So those 30 variables need to go through the database sessions (They are inputs) via a shell script. one of the variable name... (1 Reply)
Dear Unix gurus,
We have a config shell script file which has 30 variables which needs to be passed to master unix shell script that invokes oracle database sessions. So those 30 variables need to go through the database sessions (They are inputs) via a shell script. one of the variable name... (1 Reply)
I have added a new experimental "Computer Science and Mathematics Trivia - True or False" section in the discussions, currently under the tags box.
In the future, I plan to
Expand this feature to add more trivia categories from math, science and technology.
Keep track of correct and... (20 Replies)
Discussion started by: Neo
20 Replies
LEARN ABOUT ULTRIX
expr
expr(1) General Commands Manual expr(1)Name
expr - evaluate expressions
Syntax
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 The relop is one of < <= = != >= > and 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
Yields addition or subtraction of the arguments.
expr * expr
expr / expr
expr % expr
Yields multiplication, division, or remainder of the arguments.
expr : expr The matching operator compares the string first argument with the regular expression second argument; regular expres-
sion syntax is the same as that of 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
The first example adds 1 to the Shell variable a:
a=`expr $a + 1`
The second example finds the file name part (least significant part) of the pathname stored in variable a,
expr $a : '.*/(.*)' '|' $a
Note the quoted Shell metacharacters.
Diagnostics
The command returns the following exit codes:
0 The expression is neither null nor '0'.
1 The expression is null or '0'.
2 The expression is invalid.
See Alsoed(1), sh(1), test(1)expr(1)