DJGPP is a port of the Gnu C/C++ compiler to MSDOS/Windows

It requires a 386 or higher processor, and supports a flat memory model (ie there are no far or near pointers, no memory models to worry about). It provides a memory of up 128Megabytes, and automatically organises the transfer of the memory which is being accessed between disk and main memory.

Installing - ignore if you have already done the a:install

mentioned in other instructions

In order to install the system, type

	pkunzip -d a:gcc

assuming that you have loaded the first floppy into drive a: and are in the root directory on your hard disk.

A copy of PKUNZIP.EXE and of this file are on the first disk of the set.

This will ask you to insert the last disk of the set, and then the first again, before it asks for each disk in turn, building a directory structure which holds the libraries and include files for the languages.

Setting up the compiler - editing autoexec.bat

You then need to add

	\GCC\BIN

to the PATH

and the lines

SET DJGPP=C:\GCC\DJGPP.ENV

to the AUTOEXEC.BAT file

If you intend to run the compiler from a DOS window under Windows, that is all you need.

If you are running the compiler under DOS, directly, then you also need to provide a DOS Protected Mode Interface (DPMI) service Some memory management packages do this, but if not, then

	LOADHIGH C:\GCC\BIN\CWSDPMI.EXE -p

added to your AUTOEXEC.BAT after EMM.SYS and/or HIMEM.SYS will do the necessary.

Once this is done, you can use the INFO command to get further information about the DJGPP system.


        INFO 

by itself takes you into a hypertext help system

	INFO FAQ 

takes you direct to the section on Frequently Asked Questions

Ignore for C programs

Unfortunately, the version on these disks does NOT include the GXX front end for compiling C++ programs. When compiling C++ programs, it is wise to give them suffices .cc or .cpp and when linking them it is essential to specify -liostream

Thus to compile a C++ version of "Hello World", one should use

	gcc hello.cc -o hello -liostream 

and when it has successfully compiled, tow files will exist, HELLO and HELLO.EXE which is the DOS executable.

The programs supplied include many ports of UNIX utilities, such as make, sed, tar (djtar), bison (yacc), flex (lex), grep etc.