# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/^(?:"[^"]*",){1}"([^"]*)"/$1chat\/$2/gmix;t' <<< "\"01\",\"35005\",\"AL\",\"ADAMSVILLE\",86.959727,33.588437,10616,0.002627
\"05\",\"72001\",\"AR\",\"ADONA\",92.903325,35.046956,494,0.00021
\"06\",\"90804\",\"CA\",\"SIGNAL HILL\",118.155187,33.782993,36092,0.001213"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html