Visit Our UNIX and Linux User Community


if statement problem


 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers if statement problem
# 1  
Old 12-04-2005
if statement problem

hi all. i just have a very small problem. i have a menu of 7 choices. i want an if statement so that if the user chooses anything except inside the 1 to 7 range, i can handle the error for it.

i tried this:

if [ $choice -ne [1-7] ]
then
.......
fi

(but it dont work)

...any suggestions?

thanks all in advance
# 2  
Old 12-04-2005
use :-

if [[ $choice -lt 1 || $choice -gt 7 ]]
then
.....
fi

cheers
# 3  
Old 12-04-2005
LHS of "if" must be quoted.

Hi djt !

One of the reasons why your script does not work is that the left side MUST be in quotes, eg:
Code:
if [ "$number" = "1" ]; then
    echo "Number equals 1"
else
    echo "Number does not equal 1"
fi

Refer to this link for excellent explanation: http://linuxcommand.org/wss0100.php

Hope that was helpful Smilie
Regards
Graham
# 4  
Old 12-04-2005
Testing a range of values

Hi again djt !!

Try this one, this idea addresses the RH-side of the equation, namely: ranges of values:
Code:
read character
case $character in
            # Check for letters
    [a-z] | [A-Z] ) echo "Alpha range i[a-z]: You typed the letter $character"
            ;;
            # Check for digits
    [0-9] )     echo "Numeric range: 0-9: You typed the digit $character"
            ;;
            # Check for anything else
    * )         echo "You did not type a letter or a digit"
esac

Try this link for further explanations: http://linuxcommand.org/wss0120.php

Again, I hope this is usefull! Smilie
Rergards
GrahamB
# 5  
Old 12-04-2005
"-ne" is an operator to compare integer values (for being not equal). "[-7]" is a string, not an Int, this is why the test failed.

How to solve your task better has already been explained.

bakunin
 

Previous Thread | Next Thread
Test Your Knowledge in Computers #614
Difficulty: Medium
In Python, strings in double quotes work exactly the same way as strings in single quotes.
True or False?

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

Problem with If statement

Hi All, I am writing an if statement to check multiple conditions, but when I try to execute the script it is breaking at the point of if statement by showing the issue below. Code I am using is given below. if -a ] then .... else ... fi I am not understanding... (3 Replies)
Discussion started by: ginrkf
3 Replies

2. Shell Programming and Scripting

Problem if statement

echo "Enter the variable: " " read var1 echo " " for i in ib eb atm do if ; then mv properties environment.properties break else echo "No changes to $var1 " fi done When i run and enter the eb it's not working.Any suggestions please.. (7 Replies)
Discussion started by: bhas85
7 Replies

3. Shell Programming and Scripting

while statement problem

Hi, Here is a big head scratcher for me.... I'm creating a loop with while reading lines from a file called example.txt: #!/bin/sh while read line do some command > another file ----- output to another file done < example.txt I would like that another file to be unique for every... (5 Replies)
Discussion started by: svetoslav_sj
5 Replies

4. Shell Programming and Scripting

if statement problem

Writing my script and I'm banging my head on the desk right now ... My biggest problem is the 3rd IF statement where I check if the username exists. Doing the grep command on it's own in the shell gives me a 1 or 0 value. Running the script, it always returns a false value (runs the ELSE... (4 Replies)
Discussion started by: ADay2Long
4 Replies

5. UNIX for Dummies Questions & Answers

Having problem with if statement

Could someone help me out with this if statement? It's supposed to get a person's website, but it isn't working when I run it. website="" echo "Would you like to enter a website? Enter Yes/No" read choice if then while do echo "Please enter a website:"; read... (4 Replies)
Discussion started by: Sotau
4 Replies

6. Shell Programming and Scripting

if statement problem

Hi I have a bash script like this if then echo "A" else echo "B" fi $1 is something like 02350 (there is always a trailing '0') and I would like to have an if based on the value of the digits after the 0. Can anybody help? Thanks, Sarah (3 Replies)
Discussion started by: f_o_555
3 Replies

7. UNIX for Dummies Questions & Answers

if statement problem

See https://www.unix.com/shell-programming-scripting/96846-if-statement-problem.html (0 Replies)
Discussion started by: f_o_555
0 Replies

8. Shell Programming and Scripting

If Statement Problem..

The problem I am having here is that only the 1st option is executed, no matter if I pick yes or no. What am I doing wrong? How can I get this working right without resorting to a case statement? echo "This is the max size your lvol can be:" echo $MAXSIZE echo echo Do you want to max out... (2 Replies)
Discussion started by: LinuxRacr
2 Replies

9. Shell Programming and Scripting

problem with an IF statement

I need an IF statement that will compare the contents of the variable CX with the actual string "CP". ie. If the contents of $CX are NOT equal to the actual string "CP" then blah blah blah. I have tried a number of things including the following....... if ]; then if ]; then if ];... (2 Replies)
Discussion started by: hcclnoodles
2 Replies

10. UNIX for Dummies Questions & Answers

if statement problem

I keep getting an error at line 21, it doesn't like my if statement. Previously I have tried using (( )), but still get errors. The current error is that server_busy is not found. This is the script: #! /bin/ksh server_busy="na" for file in $1 $2 $3 $4 $5 $6 do echo " ${file}\t\c" ... (1 Reply)
Discussion started by: coughlin74
1 Replies

Featured Tech Videos