Re: [HEADSUP] Start of Cygwin 1.7 release cycle

[Brian Dessent <brian at dessent dot net>]

Corinna Vinschen wrote:

> They do?  How and Why?  Is that something which should be rather fixed
> in newlib instead of in the autogen configuration?

The BSD implementation of funopen() doesn't explicitly define any types
for the cookie functions, but simply says they should match the
signatures of read(2), write(2), lseek(2), and close(2).  Autogen tried
to define the following if it detected that funopen() exists:

 typedef int     (cookie_read_function_t )(void *, char *, int);
 typedef int     (cookie_write_function_t)(void *, const char *, int);
 typedef fpos_t  (cookie_seek_function_t )(void *, fpos_t, int);
 typedef int     (cookie_close_function_t)(void *);

However the newlib implementation explicitly defines these types as:

typedef ssize_t cookie_read_function_t(void *__cookie, char *__buf, size_t __n);
typedef ssize_t cookie_write_function_t(void *__cookie, const char *__buf, size_t __n);
# ifdef __LARGE64_FILES
typedef int cookie_seek_function_t(void *__cookie, _off64_t *__off, int __whence);
# else
typedef int cookie_seek_function_t(void *__cookie, off_t *__off, int __whence);
# endif /* !__LARGE64_FILES */
typedef int cookie_close_function_t(void *__cookie);

So you got an error because the types differ.  I don't see anything
wrong with the newlib definitions here, as they match the prototypes
of read/write/etc.  I'm not sure why autogen was trying to define them
using int instead of size_t or ssize_t, but that's what it was doing
and it was apparently succeeding because the BSD headers didn't have
any typedefs.

Brian