Re: Detecting DJGPP, Cygwin, Mingwin and EMX OS/2

[Eli Zaretskii]

On 24 May 2000, Akim Demaille wrote:

> Currently to find out if we are under one of these environments
> configure runs a compilation, typically to see if __CYGWIN__ is
> defined etc.
> 
> Can't we do this kind of checks *without* compiling?

For DJGPP, you can look for the variable DJDIR in the environment.  Any 
DJGPP program gets this pushed into its environment by the startup code, 
and Bash and/or M4 are no exception.

In addition, Bash will have the OS-identifier variable (I forget the 
name) which will match the string "msdosdjgpp".