Evaluating Results

Overview of the Report Window

A typical report window is shown below. It will be opened by Sync Checker after at least one mismatching object has been detected during the comparison. The upper part of the window can be used to navigate through the list of differences, the lower part is used to display the exact details of a selected mismatch.

Report Window
Report Window

The headline shows the number of different objects found. The locations of the two folders that were checked follow after that. If a previously scanned archive was used as data source, this will be mentioned. Below that, you will find an object browser, similar to the column view of the macOS Finder. Objects at the top level of the compared folders appear in the first column, objects in a subfolder at this level appear in the second column, etc. When you click onto an object, the details of the mismatch will be displayed in the lower part of the window. A text line below the browser indicates whether an ignore list was in use.

In some cases, the text Intermediate folder or no object selected will be displayed as detail information. The term “intermediate folder” should mean that Sync Checker is displaying this folder in the browser only to understand where objects inside that folder are located, helping you to navigate through the hierarchy of nested folders. The selected folder itself has not been identified as a mismatch in this case, however.

The Mismatch Filter

The switches labeled Ignore differences below the browser represent a filter setting used to show or to hide selected types of mismatches. If you set a check mark here, the respective mismatch entries will no longer be displayed in the list. For example, if you set a check mark at Missing in second folder, the report window will only show mismatching objects which have other differences. Objects with the only difference that they are missing in the second folder will temporarily disappear from the list.

Depending on what advanced options you had chosen to perform the sync check operation, the corresponding options will be selected automatically in the ignore filter and cannot be changed. For example, if you had instructed Sync Checker not to consider file system compression when comparing objects, the switch at File System Compression will be on and cannot be changed. It is clear that mismatches regarding compression cannot be contained in the result list, so unhiding (“not filtering”) these entries doesn’t make sense in this case.

The button Default Setting can be used to establish Sync Checker’s recommended display filter. Mismatch types usually unimportant will be filtered, but all other types of differences will be displayed. In case the number of mismatches is very high, Sync Checker might need a few seconds to display the updated list after the filter settings have been changed.

If you have run a Quick Check, the mismatch filter won’t be shown.

The Mismatch Details

The display in the lower half of the window shows the details of the mismatch selected in the object browser. The items at the left correspond with the first folder of the sync check, the part at the right corresponds with the second folder. Equal signs in green between entries of the two columns show items which match, “not equal” signs between entries, marked in red, indicate a mismatch. At the top you’ll see the icons of the two mismatching objects, their name, and the general type of the objects, e.g. File or Folder.

Note that a mismatch between two corresponding objects may affect more than one aspect at the same time. The red and green equality markers always indicate all types of differences found, even if you have set the display filter to ignore certain mismatch types.

The following items are shown:

Time Specifications

The time specifications for last status change, last modification and creation of a file system object are shown in the format you have specified in System Preferences. The common formats don’t consider fractions of a second. As mentioned in the chapter Comparing two Folders or Disks, some file systems store time specifications with a resolution of nanoseconds, however. If the sync check was executed with the option to respect time deviations of less that one second, the report window may indicate a respective time mismatch, but you may not see it directly.

To solve this problem, make sure the report window is active and in front, then hold the cursor over a time value. Sync Checker will then show the time specification as a help tag (“tool tip”), using the technical ISO 8601 standard. This standard is predefined to present the time with at least millisecond resolution.

For technical reasons, this feature requires macOS 10.13 High Sierra or later. It is not available in earlier versions of macOS.

The File Flags

After clicking the info icon next to the entry File Flags, Sync Checker will open an additional sheet, showing detail information about a set of attributes set at the Unix level. Check marks at the left correspond with the object of the the first folder, the switches at the right with the object from the second folder.

File Flags Details
File Flags Details

The following attributes have additional restrictions: They can only be set by the special Unix administrator “root” (the super-user) and they may only be unset by root when the system is additionally in single-user mode (depending on implementation).

Press the button Close to return to the report window.

Permission Settings

After clicking the info icon next to the lines POSIX Permissions and Access Control List, Sync Checker will open an additional sheet, showing detail information about the complete set of permission settings active for the two mismatching objects. The table at the top summarizes the permission settings for the object in the first folder, the table at the bottom the settings for the object coming from the second folder.

Permission Settings
Permission Settings

POSIX permissions and ACL entries work together to build the complete definition of permission settings that apply to a file system object. The settings presented in each table have to be read in top-down order. To determine the permissions effective for a particular user, macOS will evaluate the entries line by line and the first entry matching the user’s account and the requested right will “win”. This means if the permission settings contain contradicting entries, the entries appearing first in the table will have higher priority.

The tables contain the following columns:

Due to the complex nature of Access Control permissions, it might be necessary to show even more details about a particular entry line in the table. To do this, double-click the respective line. A drawer will open which shows the exact rights and inheritance definitions for the current object. The drawer contains the following items: The icon of the access party (user or group), the short name of that party, the permission type, the inheritance information and a list of the exact rights granted or denied by this entry.

You can close both the drawer and the sheet by pressing one of the respective Close buttons.

Access Control Entry Details
Access Control Entry Details

Extended Attributes

Each object in the file system can be associated with an unlimited number of additional data records called Extended Attributes. Each attribute has a value which can be any stream of bytes with any size. The attributes can be seen as additional content of a file next to its standard content, the data fork.

After clicking the info icon next to the line Extended Attributes, Sync Checker will open an additional sheet, showing the complete list of Extended Attributes for the two mismatching objects. The table at the left contains the attributes of the object coming from the first folder, the table at the right represents the object from the second folder.

Extended Attributes
Extended Attributes

Each attribute has a unique name which is displayed in the column Attribute Name. The sequence of bytes associated with that name is called the value of the Extended Attribute. The size of that sequence is displayed in the column Value Size. The names and values of Extended Attributes are defined by the applications which created them. Applications using Extended Attributes are, for example, the Finder, Spotlight, Time Machine, Calendar Server, and several others. Sync Checker cannot “know” in general how such attributes should be interpreted or be displayed. In the general case, Sync Checker shows the attribute value as sequence of bytes, in hexadecimal notation. To see the value, double-click the respective attribute line in the table. A special window, displaying the contents of the Extended Attribute will open. The title bar of the window shows the name of the attribute. The text box at the top shows the value of the Extended Attribute coming from the object of the first folder, the box at the bottom shows the value coming from the second folder.

Extended Attribute Contents Window
Extended Attribute Contents Window

Each text box will only display the first 4 Mebibytes of the attributes (if available). If your current user account has no access permission to read the attribute, or if one of the mismatching objects is missing in one of the folders, the text There is no Extended Attribute or you have no permission to display its contents will be displayed instead. The first column in the text box is the hexadecimal offset position in the value for which the bytes are displayed (the first byte has the position 00000000). The next 16 bytes stored at that position will be shown in the line following this offset. The bytes will additionally be shown in canonical character notation, assuming that they might represent text information encoded in the ASCII standard. Characters unprintable in the ASCII standard are represented by dots (.). The 16 characters in each line are delimited by vertical bars (|).

The Extended Attribute

macOS systems use a known Extended Attribute named to store additional information for file system objects used by the Finder. When you double-click this known attribute, Sync Checker is capable of interpreting the value. A special window will appear.

Finder Information Details
Finder Information Details

The left box in the attribute window represents the Finder information for the mismatching object in the first folder, the right box is used for the object in the second folder.

Creating a Text Report of the Mismatch List

After pressing the button with the text icon in the upper right corner of the report window, Sync Checker will create a text document summarizing the results of the sync check operation. This text can be reviewed and additionally be printed or saved as a text processing document in Rich Text Format (RTF).

Textual Report
Textual Report

In the report, the paths of the two compared folders, the current date and time, and a legend listing abbreviations used to identify types of mismatches are presented at the beginning of the document. An additional paragraph lists the ignore settings you had used for the sync check operation. Following this section, Sync Checker will list all mismatches found, in alphabetical order of the folder hierarchy. Entries are grouped by folders. Each line lists the name of the mismatching object, followed by the list of mismatch types detected for this object pair.

Press the button Print… in the document window to print or fax the report, or to create a PDF file. Press the button Save… in the window to save the text as RTF document.

Saving and Opening Sync Checker Reports

Each report window of Sync Checker behaves like a document window you know from other macOS applications. You can save the check results to a file and review them later, even on a different computer. Sync Checker uses files with the name extension .screport as type identification.

When you review a Sync Checker report “offline”, the following restriction applies: It won’t be possible to display the values of Extended Attributes if the original objects and their attributes don’t exist on the computer where the report is displayed.

Sync Checker version 3 can open documents of Sync Checker 2 and 1. However, this won’t work in the other direction: Older versions might not always be capable of interpreting the files of newer versions.