Longest line in a file

Question

I\'m looking for a simple way to find the length of the longest line in a file. Ideally, it would be a simple bash shell command instead of a script.

Answer 1

In perl:

perl -ne 'print ($l = $_) if (length > length($l));' filename | tail -1

this only prints the line, not its length too.

Answer 2

Important overlooked point in the above examples.

The following 2 examples count expanded tabs

  wc -L  <"${SourceFile}" 
# or
  expand --tabs=8 "${SourceFile}" | awk '{ if (length($0) > max) {max = length($0)} } END { print max }'

The following 2 count non expaned tabs.

  expand --tabs=1 "${SourceFile}" | wc -L 
# or
  awk '{ if (length($0) > max) {max = length($0)} } END { print max }' "${SourceFile}"

so

              Expanded    nonexpanded
$'nn\tnn'       10            5