Add an implementation of open_memstream() and open_wmemstream(). These

routines provide write-only stdio FILE objects that store their data in a
dynamically allocated buffer.  They are a string builder interface somewhat
akin to a completely dynamic sbuf.

Reviewed by:	bde, jilles (earlier versions)
MFC after:	1 month

2 files changed, 2 insertions, 0 deletions

diff --git a/include/stdio.h b/include/stdio.h
index 4fc78b8..19b1e20 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -346,6 +346,7 @@ char	*tempnam(const char *, const char *);
 FILE	*fmemopen(void * __restrict, size_t, const char * __restrict);
 ssize_t	 getdelim(char ** __restrict, size_t * __restrict, int,
 	    FILE * __restrict);
+FILE	*open_memstream(char **, size_t *);
 int	 renameat(int, const char *, int, const char *);
 int	 vdprintf(int, const char * __restrict, __va_list);
 
diff --git a/include/wchar.h b/include/wchar.h
index 9e8d807..4a3fe53 100644
--- a/include/wchar.h
+++ b/include/wchar.h
@@ -207,6 +207,7 @@ int	wcwidth(wchar_t);
 #if __POSIX_VISIBLE >= 200809 || __BSD_VISIBLE
 size_t	mbsnrtowcs(wchar_t * __restrict, const char ** __restrict, size_t,
 	    size_t, mbstate_t * __restrict);
+FILE	*open_wmemstream(wchar_t **, size_t *);
 wchar_t	*wcpcpy(wchar_t * __restrict, const wchar_t * __restrict);
 wchar_t	*wcpncpy(wchar_t * __restrict, const wchar_t * __restrict, size_t);
 wchar_t	*wcsdup(const wchar_t *) __malloc_like;