The complete program

#include <mysql/mysql.h>
#include <stdio.h>
#include <stdlib.h>

MYSQL connection;

void connect(char *server, char *dbuser, char *passw)
{
  if (!mysql_connect(&connection,server,dbuser,passw))
  {
      fprintf(stderr, "Failed to connect to database:\
              Error: %s\n",mysql_error(&connection));
      exit(2);
  }
  mysql_select_db(&connection,"m23");
};





void disconnect()
{
 mysql_close(&connection);
};




     
MYSQL_RES *query(char *sql)
{
 MYSQL_RES *res;

 if (mysql_query(&connection, sql) != 0)
    {
     fprintf(stderr, "Failed to send query: Error: %s\nsqlstatement:%s\n",\
     mysql_error(&connection),sql);
     exit(2);
    };

 res = mysql_store_result(&connection);

 return(res);
};





int main(int argc, char *argv[])
{
  MYSQL_RES *res;
  unsigned int fields;
  my_ulonglong rows;
  MYSQL_ROW row;

  connect("127.0.0.1", "root", "");

  res=query("SELECT * FROM `clients`");

  fields=mysql_field_count(&connection); //<<1

  rows=mysql_num_rows(res); //<<2


  for (int i=0; i < rows; i++)
    {
        unsigned long *lengths;

        row=mysql_fetch_row(res); //<<3

        lengths = mysql_fetch_lengths(res); //<<4

        for (int fnr=0; fnr < fields; fnr++)
            printf("[%i: %s] ", (int) lengths[fnr],
                    row[fnr] ? row[fnr] : "NULL"); //<<5
    }

  mysql_free_result(res); //<<6

  disconnect();

  return EXIT_SUCCESS;
}


root 2015-09-06