Folder Comparisons Options

 

 

This page present various criteria that can be matched to determine if folder items status, based on metadata information if possible, then by comparing file contents.

Ellié Computing Merge provides 3 preset configurations:

• Check date and size, files are considered identical only if their size and date are identical. Any difference in the date or size makes the item marked as different.
• Check files content if date or size are different, files are considered identical only if their size and date are identical. When date or size is different, the files content is compared to determine the item status.
• Always check files content, do not use metadata to determine the item status, this implies all the files contents are explicitely compared.

You can also set the criteria as you wish, and use the "Custom" configuration.

Different file sizes mean dfferent files
Equal file sizes mean equal files (dangerous)

Use the file sizes as an indication whether the file has changed or not.

 "Equal file sizes mean equal files" should be used only for files which continuously grow (for example log files)

Different dates mean different files
Equal dates mean equal files

Use the file dates as an indication whether the file has changed or not.  If you check the file dates,  you can specify more options about files and timestamp. You can also restrict the file date equality criterium is the file sizes are equal if you consider that files with the same timestamp and sizes have not be modified.

Compensate file system precision loss

The date known as the 'modification date' of each file is stored by the file system. Each file system uses some convention, for example a number of seconds since some particular date. However for the many file systems, many conventions were chosen. NTFS was built with high precision (100 nanoseconds precision), while FAT was built with 2-second only precision. Most Unix systems are precise only up to the second. Archivers as well have their own precision.
It means that whereas copying a file from place to another or simply archiving a folder should not change the files dates, it does in fact. The "compensate precision loss" option changes somewhat the comparison test so that two dates are considered equal if they are distant from less than 2 seconds (as this is the least precise format in use).
NB: if checked, this setting applies whichever timestamp comparison method is chosen

Timestamp comparison		Timestamp difference
Exact file dates	The dates should match exactly	Ignored
Fixed difference	Allow file timestamps to have a difference corresponding to +/- the value specified in the timestamp difference control.	Enter here the time difference in minutes you allow on file last-modification dates. You can choose 30 or 60 as these values correspond to both timezones and DST situations.  The timestamp difference must be less than 24 hours: only values between 1 and 1440 are valid.
Multiple difference	Allow file timestamps to have a difference corresponding to +/- several times the value specified in the timestamp difference control.

Checksums

Check the checksum algorithm the program can use if available on the local computer.
These checkboxes are useful mainly for binary comparisons and for comparison of files with respect to archived versions.
NB: these checkboxes are ignored at this time and will be used when SCM plugins and archive format plugins will become available.

Allow comparisons of files content in background

All pending file contents comparisons can be processed as a background task, so that most of the comparisons will be finished when you navigate on items.

Compare files and folders names case-sensitively

You can force folder items name to be associated case-sensitively or not. This option can be used when comparing files shared between computers where the system case sensitiveness is not the same. 

See also

• Options dialog box
• Folders Display Options
• File Name Filters Options
• File Status Filters Options
• File Date Filters Options
• 2-way Rules Options
• 3-way Rules Options