am using the book titled "Beginning Linux Programming 4th Edition by Neil Matthew
Richard Stones".
In chapter 7 of this book, i come across one example, and it is about dbm, i ran this example and i got the following error
In function `main':
ddbm1.c
.text+0x2d): undefined reference to `dbm_open'
ddbm1.c
.text+0x244): undefined reference to `dbm_store'
ddbm1.c
.text+0x2ee): undefined reference to `dbm_fetch'
ddbm1.c
.text+0x379): undefined reference to `dbm_close'
collect2: ld returned 1 exit status
I have compiled using the following commands,
1.gcc -o dbm1 -I/usr/include/ndbm dbm1.c -lgdbm
also i tried with
gcc -o dbm1 –I/usr/include/gdbm dbm1.c -lgdbm_compat –lgdbm
I am using Open Susse Linux 10.3.
I failed to find the reason behind this error, and i couldn't find the answer any where.
I hope you will assist me on this.
PHP Code:
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <ndbm.h>
/* On some systems you need to replace the above with
#include <gdbm-ndbm.h>
*/
#include <string.h>
#define TEST_DB_FILE “/tmp/dbm1_test”
#define ITEMS_USED 3
struct test_data {
char misc_chars[15];
int any_integer;
char more_chars[21];
};
int main()
{
struct test_data items_to_store[ITEMS_USED];
struct test_data item_retrieved;
char key_to_use[20];
int i, result;
datum key_datum;
datum data_datum;
DBM *dbm_ptr;
dbm_ptr = dbm_open(TEST_DB_FILE, O_RDWR | O_CREAT, 0666);
if (!dbm_ptr) {
fprintf(stderr, "Failed to open database\n");
exit(EXIT_FAILURE);
}
memset(items_to_store, '\0', sizeof(items_to_store));
strcpy(items_to_store[0].misc_chars, "“First!");
items_to_store[0].any_integer = 47;
strcpy(items_to_store[0].more_chars, "foo");
strcpy(items_to_store[1].misc_chars, "bar");
items_to_store[1].any_integer = 13;
strcpy(items_to_store[1].more_chars, "unlucky?");
strcpy(items_to_store[2].misc_chars, "Third");
items_to_store[2].any_integer = 3;
strcpy(items_to_store[2].more_chars, "baz");
for (i = 0; i < ITEMS_USED; i++)
{
sprintf(key_to_use, "%c%c%d",items_to_store[i].misc_chars[0], items_to_store[i].more_chars[0],items_to_store[i].any_integer);
key_datum.dptr = (void *)key_to_use;
key_datum.dsize = strlen(key_to_use);
data_datum.dptr = (void *)&items_to_store[i];
data_datum.dsize = sizeof(struct test_data);
result = dbm_store(dbm_ptr, key_datum, data_datum, DBM_REPLACE);
if (result != 0)
{
fprintf(stderr, "dbm_store failed on key %s\n", key_to_use);
exit(2);
}
}
sprintf(key_to_use, "bu%d", 13);
key_datum.dptr = key_to_use;
key_datum.dsize = strlen(key_to_use);
data_datum = dbm_fetch(dbm_ptr, key_datum);
if (data_datum.dptr)
{
printf("Data retrieved\n");
memcpy(&item_retrieved, data_datum.dptr, data_datum.dsize);
printf("Retrieved item - %s %d %s\n",item_retrieved.misc_chars, item_retrieved.any_integer,item_retrieved.more_chars);
}
else
{
printf("No data found for key %s\n", key_to_use);
}
dbm_close(dbm_ptr);
exit(EXIT_SUCCESS);
}
