Why does WinSCP use a .com binary for the CLI version and an .exe binary for the GUI?

I thought .com is an ancient form for executable, leftover from early MS-DOS days? Why do they use that today in WinSCP? And why only for the CLI version?

I tried asking this in their chat room, but received not a single reply for days. As always.

Solution 1:

Both WinSCP files are actually regular Win32 executables in the standard Windows PE format.

(Windows does not actually require the format to match the extension – as long as the shell detects that it is a known "executable" extension, it'll simply tell the OS to execute it, and the OS kernel itself will take care of format specifics.)

However, when Windows Cmd.exe searches %PATH% for a matching executable, it does so in the order specified by the %PATHEXT% environment variable – which lists .COM before .EXE.

So if you simply type winscp in Cmd, then the command shell will prefer to run winscp.com (which is the CLI tool) instead of winscp.exe (which is graphical).