C语言使用utlist实现的双向链表

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "utlist.h"
 
#define BUFLEN 20
 
typedef struct el {
    char bname[BUFLEN];
    struct el *next,*prev;
} el;
 
int namecmp(el *a,el *b) {
    return strcmp(a->bname,b->bname);
}
 
el *head = NULL; /* important- initialize to NULL! */
 
int main(int argc,char *argv[]) {
    el *name,*elt,*tmp,etmp;
 
    char linebuf[BUFLEN];
    int count;
    FILE *file;
 
    if ( (file = fopen( "test11.dat","r" )) == NULL ) {
        perror("can't open: ");
        exit(-1);
    }
 
    while (fgets(linebuf,BUFLEN,file) != NULL) {
        if ( (name = (el*)malloc(sizeof(el))) == NULL) exit(-1);
        strncpy(name->bname,linebuf,BUFLEN);
        DL_APPEND(head,name);
    }
    DL_SORT(head,namecmp);
    DL_FOREACH(head,elt) printf("%s",elt->bname);
    DL_COUNT(head,elt,count);
    printf("%d number of elements in listn",count);
 
    memcpy(&etmp.bname,"WESn",5);
    DL_SEARCH(head,&etmp,namecmp);
    if (elt) printf("found %sn",elt->bname);
 
    /* now delete each element,use the safe iterator */
    DL_FOREACH_SAFE(head,tmp) {
      DL_DELETE(head,elt);
    }
 
    fclose(file);
 
    return 0;
}