Re: popen()/pclose(), USE_POPEN and _POSIX_C_SOURCE

[Roberto Ierusalimschy <roberto@...>]

> for example:
> 
>         #include <unistd.h>
> 
>         ...
>         
>         #ifdef _POSIX_VERSION
>         #if _POSIX_VERSION >= 199209
>         #define USE_POPEN       1

If the system is not Posix this gets an error right in the attempt to
include unistd.h. Can we write a test that works everywhere?

-- Roberto