Nested for loop in unix shell script

Question

I am creating the shell script that will take two condition first it will get all file name in and insert one by one in html field other for loop will get the count and it will used for auto increment in serial number.

I have written code like this

cnt=`find /optware/oracle/logs/20190311_JAVA/TEMP/  -type f | wc -l`
    for ((i in `ls -l /optware/oracle/logs/20190311_JAVA/TEMP/|grep -v ^$|awk '{print $9}` && a=1; a <= $cnt ; a++)) 
    do
    echo "  <tr> $a <td></td><td>$i</td></tr>" >>Temp.lst
    done

I am getting error as && a=1: arithmetic syntax error

Kindly help me with this issue.

l0b0 · Accepted Answer · 2019-03-11 22:21:32Z

1

You can't loop over an index+value pair directly in Bash. I would write this code as follows:

index=0
for path in /optware/oracle/logs/20190311_JAVA/TEMP/*
do
    echo "  <tr>${index}<td></td><td>${path}</td></tr>" >> Temp.lst
    ((++index))
done

answered Mar 11, 2019 at 22:21

l0b0

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Comments

Ken Jackson · Accepted Answer · 2019-03-11 22:22:44Z

0

You're mixing up two looping constructs. You can use either one, but not both together.

for name [ [in [words …] ] ; ] do commands; done

and

for (( expr1 ; expr2 ; expr3 )) ; do commands ; done

answered Mar 11, 2019 at 22:22

Ken Jackson

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Comments

choroba · Accepted Answer · 2019-03-11 22:30:50Z

0

The ((...)) should contain three arithmetic expressions. in is not an arithmetic operator. In fact, it's unclear what you're trying to achieve.

To nest two loops, specify each one with its own for:

for i in `ls -l /optware/oracle/logs/20190311_JAVA/TEMP/|grep -v ^$|awk '{print $9}` ; do
    for (( a = 1 ; a <= cnt ; a++ )) ; do
        echo "$i:$a"
    done
done

If you just need a counter, there's no need for the second loop:

a=1;
for i in `ls -l /optware/oracle/logs/20190311_JAVA/TEMP/|grep -v ^$|awk '{print $9}` ; do
    echo "$i:$a"
    (( ++a ))
done

edited Mar 11, 2019 at 22:30

answered Mar 11, 2019 at 22:20

choroba

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1 Comment

Abhinav Over a year ago

the above query will return multiple output, what i want first to check how many file their in a directory suppose theiar are 10 file 10 will be the count and in other loop i will display each and and every file. the count will be used for auto increment like serial number in table. hope it should give you some idea

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