Suggestion for better and faster .net batch prologue without redundant .bat output

[SergeAgeyev]

There is some suggestions to improvement on .net batch prologue, future improvement of (#25)

It runs .exe files immediately if .exe file is located near .bat file.
It does not generate output // 2>nul || at the begin

Here is updated prologue I use, attached to hello world example:

@goto :batch_start_label_cs_hybrid
/*
@:batch_start_label_cs_hybrid
@echo off
if exist "%~dpn0.exe" (
"%~dpn0.exe" %*
exit /b %errorlevel% 
)

setlocal

:: Additional options to csc.exe (like /r:"references")
set CSC_OPS=

:: Runner options
set CS_FAIL_EXIT_CODE=1001

:: find csc.exe
set "csc="
for /r "%SystemRoot%\Microsoft.NET\Framework\" %%# in ("*csc.exe") do  set "csc=%%#"

if not exist "%csc%" (
   echo Error: no .net framework installed
   exit /b %CS_FAIL_EXIT_CODE%
)

set BAT_START_LINE=batch_start
set BAT_START_LINE=%BAT_START_LINE%_
set BAT_START_LINE=%BAT_START_LINE%label_cs_hybrid

call findstr /V "%BAT_START_LINE%" "%~dpn0.bat" > "%~dpn0.bat.cs"
if not exist "%~dpn0.bat.cs" (
   echo Error: fail to prepare executable
   exit /b %CS_FAIL_EXIT_CODE%
)

call %csc% /nologo %CSC_OPS% /out:"%~dpn0.exe" "%~dpn0.bat.cs" || (
   exit /b %CS_FAIL_EXIT_CODE%
)

del "%~dpn0.bat.cs"

"%~dpn0.exe" %*
endlocal & exit /b %errorlevel%

*/
using System;

public class Program
{
    public static int Main(string[] Argv)
    {
         Console.WriteLine("Hello, world!");
         return 0;
    }
}

I use this prologue in zip.bat utility:
https://github.com/openlab-vn-ua/BatArt/blob/master/zip.bat

[ildar-shaimordanov]

You can make it a bit shorter and better. Some improvements:

• no call for binaries
• %~f0 instead %~dpn0.bat
• add >&2 to output error messages to STDERR.
• goto :EOF is transparent for %ERRORLEVEL%, so no needs to exit /b %ERRORLEVEL%. But you can leave your original command for sure.
• no dancing around batch_start_label_cs_hybrid now. It's obviously shorter and clearer: the caret in @rem ^ tells cmd.exe to concatenate it with the next line before executing, thus you don't need to goto :LABEL and :LABEL and too complicated code to exclude the first line. And if you want, you can shorten it further replacing findstr /v /b "@rem ^" with more +1.

@rem ^
/*
@echo off

if exist "%~dpn0.exe" (
	"%~dpn0.exe" %*
	goto :EOF
)

setlocal

:: Additional options to csc.exe (like /r:"references")
set CSC_OPS=

:: Runner options
set CS_FAIL_EXIT_CODE=1001

:: find csc.exe
set "csc="
for /r "%SystemRoot%\Microsoft.NET\Framework\" %%# in ("*csc.exe") do  set "csc=%%#"

if not exist "%csc%" (
	echo Error: no .net framework installed>&2
	exit /b %CS_FAIL_EXIT_CODE%
)

findstr /v /b "@rem ^" "%~f0" >"%~f0.cs" || (
	echo Error: fail to prepare executable>&2
	exit /b %CS_FAIL_EXIT_CODE%
)

"%csc%" /nologo %CSC_OPS% /out:"%~dpn0.exe" "%~f0.cs" || (
	exit /b %CS_FAIL_EXIT_CODE%
)

del "%~f0.cs"

"%~dpn0.exe" %*
goto :EOF

*/
using System;

public class Program
{
	public static int Main(string[] Argv)
	{
		Console.WriteLine("Hello, world!");
		return 42;
	}
}

[npocmaka]

Thanks. Probably I'll have time to check it at the weekend. Is really @rem ^ works fine at the beginning of the file? It is also possible to use msbuild to reduce the redundant output: https://github.com/npocmaka/batch.scripts/blob/master/hybrids/.net/msbuild/checkPort.bat

[ildar-shaimordanov]

Is really @Rem ^ works fine at the beginning of the file?

Yes. before publishing I tested it.