DDE and Standard Makefiles

Is there any documentation on using the new StdTools makefiles that come with current versions of the DDE? I’m trying to use them to build an application and a library which both use OSLib, but it’s not clear how to add the necessary include directories and library files.

It seems to be necessary to manually edit CINCLUDES and LIBS, resulting in this Makefile for the application:

# Makefile for exampleapp

COMPONENT = ExampleApp

# The name of the linked file defaults to COMPONENT, which is often the case
# for single-file programs. But when the linked file lives in an application
# directory, it is normally called !RunImage.
TARGET = !RunImage

# The list of source/object files defaults to TARGET, which again is often
# the case for single-file programs. But we don't want our source file to be
# called !RunImage.
OBJS = main

CINCLUDES = -IC:,OSLib:

LIBS = OSLib:o.OSLib32

INSTDIR ?= <Obey$Dir>

# The shared makefiles don't attempt to guess the application directory name
# Usually you'll want to place it inside INSTDIR, which is passed in from
# either the MkInstall file, or (for !Builder builds) the components file.
# SEP expands to the directory separator character - we use this instead of
# a literal '.' character to help with cross-compilation.
INSTAPP = ${INSTDIR}${SEP}!Example

# You need to specify all the files that go into the application directory.
# The shared makefiles handle merging the various subdirectories of the
# Resources directory for you.
INSTAPP_FILES = !Boot !Run !Sprites !Sprites11 !Sprites22 !RunImage

include CApp

clean::
        ${WIPE} ${INSTAPP} ${WFLAGS}

# Dynamic dependencies:

and this for the module:

# Makefile for SFLib

COMPONENT = SFLib

TARGET = SFLib

OBJS = colpick config debug errors event general heap icons \
       menus msgs resources stack string tasks transfer url \
       windows

CINCLUDES = -IC:,OSLib:

include CLibrary

# Dynamic dependencies:

but CINCLUDES doesn’t seem to be documented anywhere and having to tack the -I on to the front feels a bit unsafe if something else also tries to update it.

Is this how it should work, or am I heading in completely the wrong direction?

ETA: I’ve found AcornC/C++.Makefiles.Docs, but it’s a little vague on specifics. Grepping the Makefile fragments for CINCLUDES suggests that nothing else tries to set it – meaning that it’s presumably safe for the user’s Makefile to do it?

Is this how it should work, or am I heading in completely the wrong direction?

The use of LIBS looks right, the key bit is that you ‘include CApp’ later on where it then appends the normal C library stubs, so it’s fine to set it to something prior to that.

CINCLUDES also looks right, since the compiler will accept multiple -I switches (eg. -IC:,MyLib: is the same as writing -IC: -IMyLib:) so could be appended to even though it currently isn’t.

This is not unlike the InetSetup plugin in RiscOS/Sources/SystemRes/InetSetup/Source/Makefile which links with OSLib.

Thanks – the fact the CINCLUDES didn’t seem to be mentioned in the comments in the example makefiles made me wonder if I was heading in the right direction.

This is not unlike the InetSetup plugin in RiscOS/Sources/SystemRes/InetSetup/Source/Makefile which links with OSLib.

Now that I’ve had a chance to properly look at the way that InetSetup builds, it seems to be expecting to find OSLib somewhere on C$Path? Also, the AppLibs Makefile defines {OSLIB} as C:OSLib.o.OSLib

Does that mean that the correct place to install OSLib for the DDE is in AcornC/C++.Export.APCS-32.Lib? Also, the 32-bit OSLib is called OSLib32 as supplied: does this need renaming to make an install ‘standard’, or is some magic filename munging going on somewhere? If I were to download and try and build InetSetup using a copy of the DDE, would I need to find and install OSLib for myself or does it somehow get installed as part of the OS sources?

Finally, if one adds additional third-party libraries to the system, is the preferred way to do it to put them into AcornC/C++.Export.APCS-32.Lib so they end up on C:, or somewhere else and update LIBS and CINCLUDES in the Makefile?

Apologies for the range of questions. I’m in the process of trying to write a tutorial (ish) for compiling an OSLib-based application in the DDE. As such, I’d prefer the installation of OSLib that I describe to match what’s considered ‘standard’ to avoid confusing things – but as a long-time GCC user, I’ve never actually had to set up the DDE properly before. It would also be better to avoid the described process being unnecessarily complicated…

Now that I’ve had a chance to properly look at the way that InetSetup builds, it seems to be expecting to find OSLib somewhere on C$Path?

Correct, C$Path is a monster variable near the top of the exports which is just a handy stepping off place for all the other libraries to be relative to. For 26 bit builds it would be within Export.APCS-R.Lib and C:OSLib.o.OSLib will still do the right thing.

Also, the 32-bit OSLib is called OSLib32 as supplied: does this need renaming to make an install ‘standard’, or is some magic filename munging going on somewhere?

The renaming is to solve the above mentioned distinction, OSLib32 goes into APCS-32 (renamed as OSLib) and OSLib goes into APCS-R, then the makefiles only ever need to refer to OSLib and the choice of target is selected by the environment (ultimately by C$Path).

The other slightly nonstandard thing to watch is that some of the headers get moved for the RISC OS build (inspect the makefile in mixed/RiscOS/Sources/ThirdParty/OSLib/Lib/OSLib). I believe its origins lie in that OSLib started out as a spare time project for Jonathan Coxhead (an Acorn employee) which got used within Acorn. When it became public it got shuffled about a bit and there are too many things tied to the internal way to be bothered changing them. It’s also worth noting it’s OSLib 6.90 which isn’t the very latest.

Finally, if one adds additional third-party libraries to the system, is the preferred way to do it to put them into AcornC/C++.Export.APCS-32.Lib so they end up on C:, or somewhere else and update LIBS and CINCLUDES in the Makefile?

I think the preferred way is to put them in either the ModuleLibs or AppLibs shared makefile as a symbol, that way they can be anywhere you want on your harddisc, any apps needing them to build just indirects via that one.

So in terms of OSLib, I think I’d ignore the one ROOL has and use the latest public one, then rename OSLib32 into the APCS-32 directory and OSLib into the APCS-R directory.