3 derp \- directory-examining recursive compare
17 recursively compares the two directories
21 using a third common backup directory
23 as reference. The changes found are printed
24 to standard output, one per line, with the file
25 status describing either side followed by tabulator
26 and the relative file path.
28 The possible status codes:
39 Both sides added different files with the
51 File was changed differently in
76 Errors are printed to standard error unless
78 option is specified. The program is terminated
79 when errors are encountered unless the
81 option is given. This can be useful if files
82 are not accessible due to file permission or
87 option will consider changes of file owner and group.
88 When omitted, file ownership is ignored.
92 option sets the octal mask
94 of bits to check in the file permissions. The default
95 ignores file permissions.
97 When modification times are comparable then the
99 option can be used to quickly find changes. If specified,
100 files are considered unchanged if the name, file size and
101 the modification time matches. This is useful when
102 comparing /n/dump archives on the same fileserver.
104 Files are considered the same if they are from the
109 matches. For directories, the access time is also
110 compared. If the access time was disabled on the
111 fileserver, then all directories need to be compared
116 Some filesystems like
118 do not always return exact file size in stat, so
119 the length check can be disabled with the
123 .B /sys/src/cmd/derp.c
131 The exit status is set to 'errors' when
132 errors were encountered.