There are a number of advantages to using projects for your applications that consist of a large number of files.
COBOL project files, .cblproj, are MSBuild files. You can use either Visual Studio or MSBuild at the command line to build your applications, if you have the .cblproj file. Having a project file that builds with MSBuild enables you to include the build commands in your builds scripts or as part of a CI.
The command to build a COBOL project from the command prompt is as follows:
MSBuild projname.cblproj
You can specify various targets and properties to use with MSBuild. Here are a few examples:
To rebuild a project for release:
MSBuild projname.cblproj /t:Rebuild /p:Configuration=Release
To build multiple projects that are part of the same solution:
MSBuild lotsofprojects.sln
To build a selection of projects, use wildcards:
MSBuild proj*.cblproj
To build a number of solutions and projects in the current directory, from the command prompt navigate to the directory that contains the projects and execute the following without any additional parameters:
MSBuild