I have a fixed-length data file where records are tagged (first 6 characters have a certain string that identifies the record) and I need to replace text from a specific line and a specific position on that line.
HEADER 123456 SHIPTO CODE 123 LANE HOUSTON TX ITEM ACME BRICK
For example, I would like to replace the ship-to code in the above data. The data can be found in positions 10-17 of the ship-to record (line starts with "SHIPTO"). I'd like to use sed or awk (or other commands) but update the data with a single command line. If there is more than one SHIPTO line, I am ok with updating them all.