Usage: patch [OPTION]... [ORIGFILE [PATCHFILE]]

Input options:

  -p NUM  --strip=NUM  Strip NUM leading components from file names.
  -F LINES  --fuzz LINES  Set the fuzz factor to LINES for inexact matching.
  -l  --ignore-whitespace  Ignore white space changes between patch and input.

  -c  --context  Interpret the patch as a context difference.
  -e  --ed  Interpret the patch as an ed script.
  -n  --normal  Interpret the patch as a normal difference.
  -u  --unified  Interpret the patch as a unified difference.

  -N  --forward  Ignore patches that appear to be reversed or already applied.
  -R  --reverse  Assume patches were created with old and new files swapped.

  -i PATCHFILE  --input=PATCHFILE  Read patch from PATCHFILE instead of stdin.

Output options:

  -o FILE  --output=FILE  Output patched files to FILE.
  -r FILE  --reject-file=FILE  Output rejects to FILE.

  -D NAME  --ifdef=NAME  Make merged if-then-else output using NAME.
  -E  --remove-empty-files  Remove output files that are empty after patching.

  -Z  --set-utc  Set times of patched files, assuming diff uses UTC (GMT).
  -T  --set-time  Likewise, assuming local time.

Backup and version control options:

  -b  --backup  Back up the original contents of each file.
  --backup-if-mismatch  Back up if the patch does not match exactly.
  --no-backup-if-mismatch  Back up mismatches only if otherwise requested.

  -V STYLE  --version-control=STYLE  Use STYLE version control.
	STYLE is either 'simple', 'numbered', or 'existing'.
  -B PREFIX  --prefix=PREFIX  Prepend PREFIX to backup file names.
  -Y PREFIX  --basename-prefix=PREFIX  Prepend PREFIX to backup file basenames.
  -z SUFFIX  --suffix=SUFFIX  Append SUFFIX to backup file names.

  -g NUM  --get=NUM  Get files from RCS or SCCS if positive; ask if negative.

Miscellaneous options:

  -t  --batch  Ask no questions; skip bad-Prereq patches; assume reversed.
  -f  --force  Like -t, but ignore bad-Prereq patches, and assume unreversed.
  -s  --quiet  --silent  Work silently unless an error occurs.
  --verbose  Output extra information about the work being done.
  --dry-run  Do not actually change any files; just print what would happen.

  -d DIR  --directory=DIR  Change the working directory to DIR first.
  --binary  Read and write data in binary mode.

  -v  --version  Output version info.
  --help  Output this help.

Report bugs to <bug-gnu-utils@prep.ai.mit.edu>.