[SOLVED] Why does CUDA.rules have two identical command lines

Why does CUDA.rules have two identical command lines

The commandline for CUDA.rules file is:

echo [CompilerPath] [Keep] [CInterleavedPTX] [ExtraNvccOptions] [Arch] -ccbin "$(VCInstallDir)bin" [Emulation] [FastMath] [Defines] -Xcompiler "/EHsc [Warning] /nologo [Optimization] /Zi [RuntimeChecks] [Runtime] [TypeInfo] [ExtraCppOptions]" [Include] [MaxRegCount] [PtxAsOptionV] [NvccCompilation] "$(InputPath)"

[CompilerPath] [Keep] [CInterleavedPTX] [ExtraNvccOptions] [Arch] -ccbin "$(VCInstallDir)bin" [Emulation] [FastMath] [Defines] -Xcompiler "/EHsc [Warning] /nologo [Optimization] /Zi [RuntimeChecks] [Runtime] [TypeInfo] [ExtraCppOptions]" [Include] [MaxRegCount] [ptxasoptionv] [NvccCompilation] "$(InputPath)""

I have put in a line for clarity as it shows two command which are identical (as far as I can see), except the first one is preceded by "echo". Does anyone know what the purpose of this is?

Solution

The first only tells you what the command is going to be, the second actually performs the command.
echo is the dos command that displays text:

C:\>echo bla bla bla
bla bla bla