我正在阅读这个页面http://dev.mysql.com/doc/refman/5.0/en/mysql-fetch-row.html,其中有一行:
printf("[%.*s] ", (int) lengths[i],
row[i] ? row[i] : "NULL");
从代码中
MYSQL_ROW row;
unsigned int num_fields;
unsigned int i;
num_fields = mysql_num_fields(result);
while ((row = mysql_fetch_row(result)))
{
unsigned long *lengths;
lengths = mysql_fetch_lengths(result);
for(i = 0; i < num_fields; i++)
{
printf("[%.*s] ", (int) lengths[i],
row[i] ? row[i] : "NULL");
}
printf("\n");
在那段代码中,[%.*s]
是什么意思?