Document return-value conventions used by this implementation, per

suggestion from Bruce.
This commit is contained in:
Tom Lane 2005-12-05 21:57:00 +00:00
parent e8c81e179e
commit 1daac8e165

View File

@ -31,7 +31,7 @@
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $PostgreSQL: pgsql/src/port/snprintf.c,v 1.30 2005/12/05 02:39:38 tgl Exp $
* $PostgreSQL: pgsql/src/port/snprintf.c,v 1.31 2005/12/05 21:57:00 tgl Exp $
*/
#include "c.h"
@ -51,9 +51,8 @@
* SNPRINTF, VSNPRINTF and friends
*
* These versions have been grabbed off the net. They have been
* cleaned up to compile properly and support for most of the Single
* Unix Specification has been added. Remaining unimplemented features
* are:
* cleaned up to compile properly and support for most of the Single Unix
* Specification has been added. Remaining unimplemented features are:
*
* 1. No locale support: the radix character is always '.' and the '
* (single quote) format flag is ignored.
@ -65,6 +64,27 @@
* 4. No support for "long double" ("Lf" and related formats).
*
* 5. Space and '#' flags are not implemented.
*
*
* The result values of these functions are not the same across different
* platforms. This implementation is compatible with the Single Unix Spec:
*
* 1. -1 is returned only if processing is abandoned due to an invalid
* parameter, such as incorrect format string. (Although not required by
* the spec, this happens only when no characters have yet been transmitted
* to the destination.)
*
* 2. For snprintf and sprintf, 0 is returned if str == NULL or count == 0;
* no data has been stored.
*
* 3. Otherwise, the number of bytes actually transmitted to the destination
* is returned (excluding the trailing '\0' for snprintf and sprintf).
*
* For snprintf with nonzero count, the result cannot be more than count-1
* (a trailing '\0' is always stored); it is not possible to distinguish
* buffer overrun from exact fit. This is unlike some implementations that
* return the number of bytes that would have been needed for the complete
* result string.
*/
/**************************************************************