Re: cygwin-1999-12-01: Prototypes in system headers not standard-compliant

[Eric Christopher <echristo at cygnus dot com>]

I'll test these out.  Does anyone have a pointer to the full Unix 98 spec?

-eric

> The prototype for read() and write() in Unix98 don't match those in
> the Cygwin header files.
>
> http://www.opengroup.org/onlinepubs/007908799/xsh/read.html
> http://www.opengroup.org/onlinepubs/007908799/xsh/write.html
>
> The standard return type for these functions is `ssize_t'.
> The traditional return type for these functions is `int'.
> The return type in Cygwin is `int'.
>
> On 32-bit platforms, like Cygwin, the best choice is probably to use
> `ssize_t' in the prototypes (they are standard, after all, right?),
> but to then have
>
> typedef int ssize_t;
>
> This is effectively what Linux does.
>
> Here's the obvious untested patch (I've never used Cygwin):
>
> --- sys/unistd.h~       Wed Dec  1 21:25:48 1999
> +++ sys/unistd.h        Fri Dec  3 20:07:58 1999
> @@ -75,10 +75,10 @@
>  pid_t   _EXFUN(_getpid, (void ));
>  int     _EXFUN(_link, (const char *__path1, const char *__path2 ));
>  off_t   _EXFUN(_lseek, (int __fildes, off_t __offset, int __whence ));
> -int     _EXFUN(_read, (int __fildes, void *__buf, size_t __nbyte ));
> +ssize_t _EXFUN(_read, (int __fildes, void *__buf, size_t __nbyte ));
>  void *  _EXFUN(_sbrk,  (size_t __incr));
>  int     _EXFUN(_unlink, (const char *__path ));
> -int     _EXFUN(_write, (int __fildes, const void *__buf, size_t __nbyte ));
> +ssize_t _EXFUN(_write, (int __fildes, const void *__buf, size_t __nbyte ));
>
>  #if defined(__CYGWIN32__) || defined(__rtems__)
>  unsigned _EXFUN(usleep, (unsigned int __useconds));
>
> --- sys/types.h~        Wed Dec  1 21:25:48 1999
> +++ sys/types.h Fri Dec  3 20:09:24 1999
> @@ -110,7 +110,7 @@
>  typedef        unsigned short  gid_t;
>  typedef int pid_t;
>  typedef        long key_t;
> -typedef long ssize_t;
> +typedef int ssize_t;
>
>  #ifdef __MS_types__
>  typedef        char *  addr_t;
>
> --- sys/_types.h~       Wed Dec  1 21:25:42 1999
> +++ sys/_types.h        Fri Dec  3 20:09:10 1999
> @@ -10,6 +10,6 @@
>  #define _SYS__TYPES_H
>
>  typedef long _off_t;
> -typedef long _ssize_t;
> +typedef int _ssize_t;
>
>  #endif /* _SYS__TYPES_H */
>
> P.S. If you do this, check all other functions for Unix98-compliance.


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