Comparison Method
It is possible to choose which method to use to compare two folders.
The method to use is strictly related to user needs; comparing source code (files only a few kilobytes large) should use a content comparison, but finding which movies (files larger than a gigabyte) are not present on the right side is faster when comparing by file size or file timestamp.
Every file is treated as binary and compared byte by byte; only ‘Compare file content ignoring line ending differences’ compares text.
The complete list of supported comparison methods is below.
| Method | Description |
|---|---|
| Compare file sizes Very quick |
Two files are identical if they have the same file size |
| Compare file timestamps Very quick |
Two files are identical if they have the same timestamp.
The Unix last modified date is used for comparison. If file A's timestamp is less than file B's it is marked as older and it will be shown with a different color. It is possible to set a span in seconds to consider two files with the same timestamp, see below |
| Compare file timestamps and sizes Very quick |
Compare the file timestamps; only if they are different compare the size. |
| Compare file content only Slow on large files |
Compare files as binary, byte by byte |
| Compare file timestamp, size and content Slow on large files |
Compare the file content; only if the content is different compare the timestamp, and only if the timestamp differs compare the size |
| Compare file content ignoring line ending differences Slow on large files |
Compare files as plain text, reading line by line and comparing lines. The line ending character is ignored so a DOS file (with lines separated by CR+LF) matches a Unix file (with lines separated by LF) if, ignoring the newlines, the content is identical |
Compare Finder Metadata
It is possible to compare macOS Finder Metadata.
When the metadata comparison mismatches (for example, the left file’s label is red and the right file’s label is blue), the other comparison methods (size, timestamp, content) are not evaluated.
The complete list of supported metadata
| Metadata | Description |
|---|---|
| Label | Compare all labels assigned to a file |
| Tags Available in macOS 10.9 or above |
Compare all tags assigned to a file |
Folders Traversal
Users can choose not to traverse special files like symbolic links and packages.
| File | Description |
|---|---|
| Follow Symbolic Links | If checked, symbolic links will be traversed |
| Skip Packages | If checked, special macOS files (so-called bundles or packages)
like Applications and Frameworks will not be traversed |
| Check Resource Forks | Checks if files are resource forks; this can slow down the comparison. When this option is on, if the file is a resource fork its size is determined from its structured data. |
Timestamp Tolerance
The timestamp comparison considers two files matching when the time (including the seconds) is identical, but sometimes it is useful to have a tolerance range, for example when the difference is around 5 seconds.
You can set this tolerance by entering a positive integer number into the text field Ignore differences of X seconds or less.
Choose Files to View according to differences found
After the comparison completes you can choose which files to view.
Definition: Orphan indicates a file present only on one side.
The complete list of show options is below.
| Choice | Description |
|---|---|
| Show All | No matter the comparison result, show files |
| Only Mismatches | Show only files with some mismatch (size, timestamp or content) |
| Only Matches | Show only identical files |
| No Orphans | Show files present both on left and right sides |
| Only Orphans | Show files present only on left or only on right |
Choose Folders to View
It is possible to hide empty and orphan folders.
Folders can be empty because they don’t contain any files on disk or because all files/folders inside them are filtered.
Orphan folders are present only on one side (left or right).
Show Filtered Files
When a filter finds matches the elements are not visible, but if it’s necessary to show them you can click on the Filtered button.
Default filters can be changed or totally deleted from Session Preferences window.
Some files are excluded by default; the complete list is shown below.
| Description | File |
|---|---|
| Backup and system files | .DS_Store, *~ |
| Version Control System files | CVS, .svn, .git, .hg, .bzr |