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How to check the number of columns in a line??

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Top Forums Shell Programming and Scripting How to check the number of columns in a line??
# 15  
Old 10-18-2013
can you explain me the below command

Code:
awk -F\| 'NF != 6 {exit 1}' file1.txt || test=1

|| is a OR condition so

Code:
0 0 = 0
0 1 = 1
1 0 = 1
1 1 = 1

1 = true
0 = false

so if the file1.txt is not having 6 columns in each of the row, awk -F\| 'NF != 6 {exit 1}' file1.txt will exit with 1 (condition is true). if the first condition evaluates to true, then it wont evaluate the 2nd condition i.e test=1. but it is evaluating. and setting test=1.
# 16  
Old 10-18-2013
I guess not sure you are getting old values, did you unset variable test for each loop iteration ?
if not do like this
unset test
# 17  
Old 10-18-2013
i have kept the above awk line inside a shell script. and before executing the script i am setting test=0. when the shell script completes. test doesnot exist.

Code:
file=$1
test=0
echo "test: $test"
awk -F\| 'NF != 6 {exit 1}' $file || test=1
if [ $test -eq 1 ]; then
        echo "test = 1"
elif [ $test -eq 0 ]; then
        echo "file is OK"
fi

# 18  
Old 10-18-2013
I can't reproduce that on cygwin. Could you post an example input file?
# 19  
Old 10-18-2013
the command is working fine.
Code:
awk -F\| 'NF != 6 {exit 1}' $file || test=1

just want to know how the condition gets evaluated?
refer my second last (#15) post.

any ways my input file is like
correct input file:
Code:
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123

for the above file test will be = 0

false input file:
Code:
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz
111|abc|xxx|yyy|zzz|123

for the above input file test will be equal to 1
# 20  
Old 10-18-2013
That isn't what you said before?
Quote:
if the first condition evaluates to true, then it wont evaluate the 2nd condition i.e test=1 .
is correct, but
Quote:
but it is evaluating. and setting test=1 .
Is it setting test when it shouldn't, or not?
# 21  
Old 10-18-2013
OR works like this:
Code:
 command1 || command2 
  command2 is executed if, and only if, command1 returns a non-zero exit status.

I think it was mentioned earlier by others.
Code:
test=0;awk -F\| 'NF != 6 {exit 1}' INPUT || test=1 && echo $test

Code:
can INPUT
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123

Code:
test=0;awk -F\| 'NF != 6 {exit 1}' INPUT || test=1 && echo $test

Code:
cat INPUT
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz|123
111|abc|xxx|yyy|zzz
111|abc|xxx|yyy|zzz|123

Line 5 has 5 fields and awk exits with exit status 1. Hence variable test gets value 1.
( and it prints in my example )
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