diffutils: Reject Names

 
 10.10 Reject File Names
 =======================
 
 The names for reject files (files containing patches that 'patch' could
 not find a place to apply) are normally the name of the output file with
 '.rej' appended (or '#' if using '.rej' would make the backup file name
 too long).
 
    Alternatively, you can tell 'patch' to place all of the rejected
 patches in a single file.  The '-r REJECT-FILE' or
 '--reject-file=REJECT-FILE' option uses REJECT-FILE as the reject file
 name.