A tool to evaluate methods in creating temp files

tools/win/CreateTempFilesPerfEvaluation/ReadMe.txt

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+[Motivation]
+This tool is to compare the time cost of creating temporary files between using
+GetTempFileName() Windows API and using the GUID-based method, especially when 
+there are already tens of thousands of temporary files in the target directory.
+
+The problem setting can be referred to 
+https://bugs.chromium.org/p/chromium/issues/detail?id=711534
+
+[How to use it]
+Please download the files (.cc, .sln, .vcxproj) and compile the code in Visual 
+Studio. Run "CreateTempFilesPerfEval.exe" either from the build directory or 
+from Visual Studio. No parameters are needed. This tool allows interaction with 
+the users. Once launched, you will see the following message on the console:
+
+"Please enter # of files to create 
+(maximum 65535), or "quit" to end the program :" 
+
+Simply type in a number less than 65536 (e.g. 1000) and you will see:
+
+"Please select method to create temp file names,
+"t" for GetTempFileName
+"g" for GUID-based
+"b" for both
+or "quit" to end the program :"
+
+Just select the method(s) you want to try (e.g., "b"), and you will get output 
+like below:
+
+GetTempFileName :
+500 / 1000 --- 434 ms
+1000 / 1000 --- 408 ms
+File creation succeeds at 
+C:\Users\chengx\AppData\Local\Temp\TempDirGetTempFileName\, now clean all of them!
+C:\Users\chengx\AppData\Local\Temp\TempDirGetTempFileName\ directory is deleted!
+
+GUID-based :
+500 / 1000 --- 423 ms
+1000 / 1000 --- 429 ms
+File creation succeeds at 
+C:\Users\chengx\AppData\Local\Temp\TempDirGuid\, now clean all of them!
+C:\Users\chengx\AppData\Local\Temp\TempDirGuid\ directory is deleted!
+
+It shows the time cost of creating every 500 temp files in milliseconds.
+
+The temporary directories are created in the "Temp" directory as shown above.
+The temp files are then created in the newly created temporary directories.
+All of them are deleted by the program automatically. If the deletion fails for 
+some reason, you will see:
+
+"[Attention] C:\Users\chengx\AppData\Local\Temp\TempDirGuid\ directory's deletion
+fails, please take a look by yourself!" 
+
+