How to write if loop in unix


 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers How to write if loop in unix
# 1  
Old 07-25-2007
How to write if loop in unix

Hi Thanks to one who helped me to create a new thread
I am so new to unix and trying to learn the stuff
Thanks for all the help I am getting here
I wanted to execute if loop like

if( x=y || (x=z && x=q))
{
some statements
}

Can I get help how to do write the if loop in unix shell scripting
I know if it is for two like
if [[ x eq y || x eq z ]] but couldn't do it with the above requirement

Thanks in advance
PINKY
# 2  
Old 07-25-2007
Here is one form of looping:
Code:
#!/bin/ksh
typeset -i mCnt=0
while [ ${mCnt} -le 10 ]
do
  echo "Count = "${mCnt}
  mCnt=${mCnt}+1
done

# 3  
Old 07-25-2007
the syntax depends on the shell you are using...

in the korn shell an if statement looks like:

if [ $a = $b]
then
.....
else
.....
fi
# 4  
Old 07-25-2007
Data

Thanks for the answers
That didn't help me
I want if statement for exactly this condition
if(x=y || (y=z && a=b))

I was looking to write ksh script

Thanks again
Pinky
# 5  
Old 07-25-2007
Pinky,
Your 'if' statement is not clear on to what type the variables x,y,z,a,b are.

It makes a difference if they are string or numeric.

Numeric:
Code:
x=1
y=1
z=3
a=9
b=8
if [ $x -eq $y -o \( $y -eq $z -a $a -eq $b \) ]; then
 echo "FOUND NUMERIC"
else
 echo "NOT FOUND NUMERIC"
fi

Alphanumeric:
Code:
X='A'
Y='A'
Z='C'
A='M'
B='N'
if [ "$X" = "$Y" -o \( "$Y" = "$Z" -a "$A" = "$B" \) ]; then
 echo "FOUND CAPITAL ALPHA"
else
 echo "NOT FOUND CAPITAL ALPHA"
fi

# 6  
Old 07-25-2007
Thanks I am sorry not to be clear that's for numeric
It worked perfect

Thanks for all your help
 
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

How to write a Boolean variable which succeed and failed inside the if loop in shell script ?

I have if loop with multiple variable value check in if loop. How can i print only if loop satisfied variable and its value in shell script ? I dont want to check each variable in if loop. That makes my script larger. if ] then echo "Only satisfied variable with value" ... (3 Replies)
Discussion started by: prince1987
3 Replies

2. UNIX for Dummies Questions & Answers

Write a while loop inside for loop?

I'm taking a unix class and need to countdown to 0 from whatever number the user inputs. I know how to do this with a while or until loop but using the for loop is throwing me off.... I know I can use an if-then statement in my for loop but can I include a while loop in my for loop? (3 Replies)
Discussion started by: xxhieixx
3 Replies

3. Shell Programming and Scripting

how to write for loop

Hi All, I have one variable "TABLE_LIST" having the values and each valeus i can run in for loop like below: TABLE_LIST= abc,abcd,acbfd i should write the for loop and use each value at a time . Please help me Thanking in advance .............. Regards, Dathu (4 Replies)
Discussion started by: pdathu
4 Replies

4. UNIX for Dummies Questions & Answers

Unable to write to a file within a loop

Hi All, Following is the program that i have written in cygwin. The redirection of the unfound $param1 to error.txt file doesnt work.Can any one help? #!/usr/bin/sh fname=$1 sed 's/ //g' "$fname" > fname1 while read i do echo $i > file1 #param1 is script name ... (1 Reply)
Discussion started by: janardhanamk
1 Replies

5. IP Networking

read/write,write/write lock with smbclient fails

Hi, We have smb client running on two of the linux boxes and smb server on another linux system. During a backup operation which uses smb, read of a file was allowed while write to the same file was going on.Also simultaneous writes to the same file were allowed.Following are the settings in the... (1 Reply)
Discussion started by: swatidas11
1 Replies

6. Shell Programming and Scripting

Push records to array during implicit loop and write to file

NEWBIE ALERT! Hi, I'm 1 month into learning Perl and done reading "Minimal Perl" by Tim Maher (which I enjoyed enoumously). I'm not a programmer by profession but want to use Perl to automate various tasks at my job. I have a problem (obviously) and are looking for your much appreciated help.... (0 Replies)
Discussion started by: jospan
0 Replies

7. Shell Programming and Scripting

Need to write a script to reformat a file in unix but not familiar with unix

unix script must do the fiollowing open a file containing comma delimited records > each record contains 10 fields > removes the 2nd field and use that same field containing fields 2 to 10 the original record after fprocessing should containing fields 1 and 3 a new erecord must be... (10 Replies)
Discussion started by: dwightja
10 Replies

8. Shell Programming and Scripting

How to write a If loop..

Hi all.. I've written a script which reads all system backup information. #!/bin/ksh export ORACLE_SID=$1 export primaryhost=$2 export sid=`echo $ORACLE_SID| tr ` RESULTFILE=/oracle/PC9/backupstatus_prod.log ssh -l ora${sid} ${primaryhost} "tail -1... (2 Replies)
Discussion started by: suri.tyson
2 Replies

9. Shell Programming and Scripting

trying to write a script to loop through a port info file

Below is part of a script i have written to loop through part of a port info file. How do i continue the script to get info for OS Device Name, manufacturer and then put information into an array? HBA Port WWN: 10000000c9420b4b OS Device Name: /dev/cfg/c10 Manufacturer: Emulex... (5 Replies)
Discussion started by: rcon1
5 Replies

10. Programming

how to write c codes in UNIX

Sorry for asking a very basic question. How do i compile my c codes in UNIX. That is how do i know whether any c compiler is there in my system? If nothing is present where from do i get one and load into my system? (12 Replies)
Discussion started by: rraajjiibb
12 Replies
Login or Register to Ask a Question