fetch.c

UNIX编程高级环境（第二版）的网络套接字部分的程序源码

#include    "db.h"

/* Fetch a specified record.
 * We return a pointer to the null-terminated data. */

char *
db_fetch(DB *db, const char *key)
{
    char    *ptr;

    if (_db_find(db, key, 0) < 0) {
        ptr = NULL;                /* error, record not found */
        db->cnt_fetcherr++;
    } else {
        ptr = _db_readdat(db);    /* return pointer to data */
        db->cnt_fetchok++;
    }
            /* Unlock the hash chain that _db_find() locked */
    if (un_lock(db->idxfd, db->chainoff, SEEK_SET, 1) < 0)
        err_dump("un_lock error");
    return(ptr);
}