Like @code{sprintf}, but instead of passing a pointer to a buffer, you
pass a pointer to a pointer. This function will compute the size of
the buffer needed, allocate memory with @code{malloc}, and store a
pointer to the allocated memory in @code{*@var{resptr}}. The value
returned is the same as @code{sprintf} would return. If memory could
Like @code{sprintf}, but instead of passing a pointer to a buffer, you
pass a pointer to a pointer. This function will compute the size of
the buffer needed, allocate memory with @code{malloc}, and store a
pointer to the allocated memory in @code{*@var{resptr}}. The value
returned is the same as @code{sprintf} would return. If memory could