Cannot select a dividing line with a two-column separator

Question

I am trying to do the following:

• Read the file line by line.
• Each row has the following structure: field1;field2;field3
• Use awk to separate each of these fields, and then process each of these fields further.

The code snippet I have is:

 while read l do n=`echo ${l} | awk --field-separator=";" '{print NF}'` field1=`echo ${l} | awk --field-separator=";" '{print $1}'` field2=`echo ${l} | awk --field-separator=";" '{print $2}'` field3=`echo ${l} | awk --field-separator=";" '{print $3}'` echo ${n} ${field1} ${field2} ${field3} done < temp 

If temp contains only the following line:

 xx;yy;zz 

The answer I get on the command line is:

 1 xx;yy;zz 

I am not sure I understand this conclusion. Any explanation would be nice, given that it works for other files. I am working on a Mac while this code uses awk inside a bash script.

Answer 1

Your awk does not know what --field-separator=";" when you do this:

 awk --field-separator=";" '{print $1}' 

your awk still uses FS by default space, and so $ 1 contains the entire input line, and $ 2 and $ 3 are empty. Use -F';' to install FS.

You are the WAY, WAY from the label in how to write the script you want. If you tell us more about what “process each field” is, we can help you.

Answer 2

Why awk when you can do this in pure bash?

 while IFS=';' read -r field1 field2 field3; do echo "Field1: $field1" echo "Field2: $field2" echo "Field3: $field3" done < file.txt 

Or, if you do not know the number of fields:

 while IFS=';' read -ra fields; do echo "Number of fields: ${#fields[@]}" echo "Field1 ${fields[0]}" done < file.txt 

Answer 3

This is probably a bug with your awk. Try other formats:

 while read l do n=`echo "${l}" | awk -F\; '{print NF}'` field1=`echo "${l}" | awk -F\; '{print $1}'` field2=`echo "${l}" | awk -F\; '{print $2}'` field3=`echo "${l}" | awk -F\; '{print $3}'` echo "${n} ${field1} ${field2} ${field3}" done < temp 

or

 while read l do n=`echo "${l}" | awk -v 'FS=;' '{print NF}'` field1=`echo "${l}" | awk -v 'FS=;' '{print $1}'` field2=`echo "${l}" | awk -v 'FS=;' '{print $2}'` field3=`echo "${l}" | awk -v 'FS=;' '{print $3}'` echo "${n} ${field1} ${field2} ${field3}" done < temp 

or

 while read l do n=`echo "${l}" | awk 'BEGIN{FS=";"}{print NF}'` field1=`echo "${l}" | awk 'BEGIN{FS=";"}{print $1}'` field2=`echo "${l}" | awk 'BEGIN{FS=";"}{print $2}'` field3=`echo "${l}" | awk 'BEGIN{FS=";"}{print $3}'` echo "${n} ${field1} ${field2} ${field3}" done < temp 

Try other awks like mawk or nawk .