How do I use this command in a pre build event in Visual Studio

Question

I will be concise.

The command FOR /F %i IN (C:\Version.txt) DO @set Version=%i works perfectly fine in cmd.exe to read the text of the file into a variable. but whenever I put that line into a prebuild event in Visual Studio it says Exited with code 255.

On http://msdn.microsoft.com/en-us/library/windows/desktop/ms681382(v=vs.85).aspx I found that 0xFF / 255 means: The extended attributes are inconsistent..

How do I use that command in a pre build event? Many thanks.

Answer 1

The correct syntax is

FOR /F %%i IN (C:\Version.txt) DO @set Version=%%i

However this will not work as you epxect: VS spawns a cmd.exe process to execute build events, meaning that if you set a variable it is local to that cmd.exe only, hence the rest of your build will not have access to Version.

Luckily there are much better alternatives than batch files: if you're using VS2010 or higher, the project files are msbuild files, so to get all possible versioning things working you just create a common msbuild script to do whatever you need to do with the version (eg create a .res file if it's for C++, or modify the AssemblyInfo.cs for C#) and include it in all your projects.