wrjpgcom inserts a textual comment in a JPEG file.
You can add to or replace any existing comment(s).
Usage: wrjpgcom [switches] [inputfile]
Switches (names may be abbreviated):
  -replace         Delete any existing comments
  -comment "text"  Insert comment with given text
  -cfile name      Read comment from named file
Notice that you must put quotes around the comment text
when you use -comment.
If you do not give either -comment or -cfile on the command line,
then the comment text is read from standard input.
It can be multiple lines, up to 65000 characters total.
You must specify an input JPEG file name when supplying
comment text from standard input.