From the wiki:
[Check out for] Synchronize
Identifies the versions of the files in the client file system by using the signature file. Versions are checked out only if the signature file shows:
- Client files that differ from their corresponding CA Harvest SCM versions.
- Client files with timestamps that differ from their corresponding timestamps in the signature file.
Items are checked out in a read-only mode.
Note: The check-out for synchronize mode is useful in the build process. This option compares the version on the file system with the version in the database. If the database version contains a newer timestamp, the file is checked out.
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In this process the harvest.sig (signature) file found in every folder where files are checked out is very important. If this file is missing, then every file in the folder is checked out, just like a Check Out for Browse.
On a Windows system, you can look in your check-out folder to find all the signature files with a command like this:
dir /b/s/ah <check out folder>\harvest.sig
Here's an example:
C:\Users\Administrator>dir /b/s/ah c:\Temp\harvest.sig
c:\Temp\DOCS\harvest.sig
c:\Temp\EXE\harvest.sig
c:\Temp\OBJ\harvest.sig
c:\Temp\SRC\harvest.sig
c:\Temp\SRC\DXY\harvest.sig
c:\Temp\SRC\HPGL\harvest.sig
c:\Temp\TESTDATA\harvest.sig
c:\Temp\TESTDATA\DXYTEST\harvest.sig
c:\Temp\TESTDATA\HPGLTEST\harvest.sig
On Unix and Linux, the same can be accomplished like this:
find <check out folder> -name .harvest.sig 2>/dev/null
Here's an example:
[cascm@scm-broker scm]$ find /home/cascm/temp -name .harvest.sig 2>/dev/null
/home/cascm/temp/TESTDATA/.harvest.sig
/home/cascm/temp/TESTDATA/DXYTEST/.harvest.sig
/home/cascm/temp/TESTDATA/HPGLTEST/.harvest.sig
/home/cascm/temp/SRC/HPGL/.harvest.sig
/home/cascm/temp/SRC/.harvest.sig
/home/cascm/temp/SRC/DXY/.harvest.sig
/home/cascm/temp/EXE/.harvest.sig
/home/cascm/temp/DOCS/.harvest.sig
/home/cascm/temp/OBJ/.harvest.sig
You can also read the contents of the signature file with a command called "hsigget". Here's where you can read more about this: hsigget Command-Signature File Query - CA Harvest SCM - 13.0 - CA Technologies Documentation
You can read more about checking in and checking out here: Use Check-In and Check-Out in CA Harvest SCM - CA Harvest SCM - 13.0 - CA Technologies Documentation
Let me know if you need more details.