My implementation of a 'file_is_binary' function.

gistfile1.txt

# Some lines may be dependent on my framework and need to be removed or modified. Easy enough to do.
function file_is_binary {
   # Return true if file is binary, false if not.
   # >>> file_is_binary "file"
   ${arcRequireBoundVariables}
   typeset file 
   file="${1:-}"
   file_raise_file_not_found "${file}" && ${returnTrue} 
   [[ ! -s "${file}" ]] && ${returnFalse} 
   if boot_does_program_exist "perl"; then
      if perl -E 'exit((-B $ARGV[0])?0:1);' "${file}"; then
         ${returnTrue} 
      else
         ${returnFalse} 
      fi
   else
      if (( $(diff "${file}" /etc/passwd | grep "Binary files" | wc -l) )); then
         ${returnTrue}
      else
         ${returnFalse} 
      fi
   fi
}