less-579 will not compile under Windows

[jftuga]

To compile , I am using:

"C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat"
nmake /f Makefile.wnm

• less-576 will compile
• less-577 will not

Here is the less-576 compilation error message:

lsystem.obj : error LNK2019: unresolved external symbol tty_device referenced in function lsystem
less.exe : fatal error LNK1120: 1 unresolved externals

Here is the difference in lsystem.c:

diff less-576\lsystem.c less-577\lsystem.c

121c121
<       if (__open("/dev/tty", OPEN_READ) < 0)
---
>       if (__open(tty_device(), OPEN_READ) < 0)
123c123
<       if (open("/dev/tty", OPEN_READ) < 0)
---
>       if (open(tty_device(), OPEN_READ) < 0)

In the less-579 code, I reverted these back to using "/dev/tty" and the compilation was then successful. However, I doubt this is the best fix for this problem and therefore did not submit a PR. I suspect that the tty_device() function needs to be changed, but I did not have time to further investigate.

[gwsw]

I'm not sure what you mean by "v579" -- that tag has not yet been built. In any case, this bug should be fixed in 0c08883.

[jftuga]

I was testing with this:

http:https://greenwoodsoftware.com/less/less-579.tar.gz

This tarball actually includes the 0c08883 patch, but still fails to compile.

[gwsw]

Ah, sorry, I'm still in the process of preparing v579 and forgot that that had been uploaded.

Well, that's strange that you're getting that error with that code, since the call to tty_device is surrounded by

#if !MSDOS_COMPILER

MSDOS_COMPILER should be WIN32C (3) if you build with Makefile.wnm.

[jftuga]

Is there anyway I can tell if that is actually set or not?

[gwsw]

You could try something like this:

   inp = dup(0);
    close(0);
+#define _XSTR(x) _STR(x)
+#define _STR(x) #x
+#warning "MSDOS_COMPILER is " _XSTR(MSDOS_COMPILER)
+#pragma message "MSDOS_COMPILER is " _XSTR(MSDOS_COMPILER)
 #if !MSDOS_COMPILER
 #if OS2
    /* The __open() system call translates "/dev/tty" to "con". */

[jftuga]

That did not work but I think I found something similar:

#define STRINGIFY( L )       #L
#define MAKESTRING( M, L )   M(L)
#define STRINGIZE(X)         MAKESTRING( STRINGIFY, X )
#pragma message( "You have " STRINGIZE(MSDOS_COMPILER) )

When compiling, this was returned:

You have 3

Please let me know if my replacement is not what you are looking for.

[gwsw]

So you have MSDOS_COMPILER == 3, but the code inside #if !MSDOS_COMPILER is being compiled? That's difficult to understand.

[jftuga]

I agree. I am not sure what to make of it. Do the define and pragma statements that I previously posted look OK to you?

[gwsw]

Yes they look ok, and 3 (WIN32C) is the value I would expect MSDOS_COMPILER to be set to (defined in defines.wn). I don't understand why code under #if !MSDOS_COMPILER would be compiled. That construct is used elsewhere, for example in screen.c, where it must be working.

[jftuga]

Could you add something like

#if MSDOS_COMPILER == 3

I don't know / remember a lot about C preprocessor statements.

[gwsw]

Please check whether https://greenwoodsoftware.com/less/less-580.tar.gz works for you.

[jftuga]

Please check whether https://greenwoodsoftware.com/less/less-580.tar.gz works for you.

Version 580 compiles:

03/03/2021  04:21 PM           327,168 less.exe
03/03/2021  04:21 PM           143,872 lesskey.exe

Version check:

.\less.exe --version
less 580 (Spencer V8 regular expressions)

Thank you for working on this with me. I really appreciate it. How did you fix it?