Converting Tab delimited file to Comma delimited file in Unix

then this command will do

sed 's/ /,/g' filename

or

tr " " "," < filename

I can see some extra spaces at the last of each line. If you don't want a comma at the last then you can strip the extra space and convert. The below will do that

sed -e 's/^\(.*\) $/\1/' -e 's/ /,/g' filename

sed 's/[[:space:]]\{1,\}/,/g' tab_del

yes correct, you have spaces in between fields....

try this

sed 's/ [ ]*/,/g' tab_del