FILE

       -S, --starting-file=FILE
              start with FILE when comparing directories

       --from-file=FILE1
              compare FILE1 to all operands; FILE1 can be a directory

       --to-file=FILE2
              compare all operands to FILE2; FILE2 can be a directory

       -i, --ignore-case
              ignore case differences in file contents

       -E, --ignore-tab-expansion
              ignore changes due to tab expansion

       -Z, --ignore-trailing-space
              ignore white space at line end

       -b, --ignore-space-change
              ignore changes in the amount of white space

       -w, --ignore-all-space
              ignore all white space

       -B, --ignore-blank-lines
              ignore changes where lines are all blank

       -I, --ignore-matching-lines=RE
              ignore changes where all lines match RE

       -a, --text
              treat all files as text

       --strip-trailing-cr
              strip trailing carriage return on input

       -D, --ifdef=NAME
              output merged file with ’#ifdef NAME’ diffs

       --GTYPE-group-format=GFMT
              format GTYPE input groups with GFMT

       --line-format=LFMT
              format all input lines with LFMT

       --LTYPE-line-format=LFMT
              format LTYPE input lines with LFMT

              These format options provide fine-grained control over the output

              of diff, generalizing -D/--ifdef.

       LTYPE is ’old’, ’new’, or ’unchanged’.
              GTYPE is LTYPE or ’changed’.

              GFMT (only) may contain:

       %<     lines from FILE1

       %>     lines from FILE2

       %=     lines common to FILE1 and FILE2

       %[-][WIDTH][.[PREC]]{doxX}LETTER
              printf-style spec for LETTER

              LETTERs are as follows for new group, lower case for old group:

       F      first line number

       L      last line number

       N      number of lines = L-F+1

       E      F-1

       M      L+1

       %(A=B?T:E)
              if A equals B then T else E

              LFMT (only) may contain:

       %L     contents of line

       %l     contents of line, excluding any trailing newline

       %[-][WIDTH][.[PREC]]{doxX}n
              printf-style spec for