Change go version to 1.20 for Windows 7 support

scripts/README.md

@@ -1,3 +1,11 @@
+## Versions
+
+[Go 1.20](https://go.dev/doc/go1.20) is last version with support Windows 7 and macOS 10.13.
+Go 1.21 support only Windows 10 and macOS 10.15.
+
+So we will set `go 1.20` (minimum version) inside `go.mod` file. And will use env `GOTOOLCHAIN=go1.20.14` for building
+`win32` and `mac_amd64` binaries. All other binaries will use latest go version.
+
 ## Build
 
 - UPX-3.96 pack broken bin for `linux_mipsel`

scripts/build.cmd

@@ -1,15 +1,18 @@
 @ECHO OFF
 
+@SET GOTOOLCHAIN=
 @SET GOOS=windows
 @SET GOARCH=amd64
 @SET FILENAME=go2rtc_win64.zip
 go build -ldflags "-s -w" -trimpath && 7z a -mx9 -sdel %FILENAME% go2rtc.exe
 
+@SET GOTOOLCHAIN=go1.20.14
 @SET GOOS=windows
 @SET GOARCH=386
 @SET FILENAME=go2rtc_win32.zip
 go build -ldflags "-s -w" -trimpath && 7z a -mx9 -sdel %FILENAME% go2rtc.exe
 
+@SET GOTOOLCHAIN=
 @SET GOOS=windows
 @SET GOARCH=arm64
 @SET FILENAME=go2rtc_win_arm64.zip
@@ -47,11 +50,13 @@ go build -ldflags "-s -w" -trimpath -o %FILENAME% && upx %FILENAME%
 @SET FILENAME=go2rtc_linux_mipsel
 go build -ldflags "-s -w" -trimpath -o %FILENAME% && upx %FILENAME%
 
+@SET GOTOOLCHAIN=go1.20.14
 @SET GOOS=darwin
 @SET GOARCH=amd64
 @SET FILENAME=go2rtc_mac_amd64.zip
 go build -ldflags "-s -w" -trimpath && 7z a -mx9 -sdel %FILENAME% go2rtc
 
+@SET GOTOOLCHAIN=
 @SET GOOS=darwin
 @SET GOARCH=arm64
 @SET FILENAME=go2rtc_mac_arm64.zip