我不知道为什么我收到此错误联系起来,我敢肯定一切都正确连接不知道为什么我得到一个链接错误
gcc -Wall -Wextra -o test driver.c target.c
driver.c:8: warning: unused parameter ‘argc’
ld: duplicate symbol _first in /var/folders/yx/31ddgzsj4k97jzvwhfx7tkz00000gn/T//ccw2n48G.o and /var/folders/yx/31ddgzsj4k97jzvwhfx7tkz00000gn/T//ccKZdUlG.o for architecture x86_64
collect2: ld returned 1 exit status
我有以下的代码,这是一个简单的链表,但我不知道为什么它不会编译
driver.c
#include "target.h"
#include <stdio.h>
#include <stdlib.h>
char * prog;
int main(int argc, char * argv[]){
prog = argv[0];
print_target_list(1);
.....
target.c
#include "target.h"
/* This function returns true if there is a target with name in the target linked list */
bool is_target(char * name){
struct target_node * ptr = first;
while(ptr != NULL){
if(strcmp(ptr->name,name) == 0){
return true;
}
ptr = ptr->next;
}
return false;
}
......
target.h
#ifndef TARGET_H
#define TARGET_H
//#include "source.h"
#include <stdbool.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
/*-----------------------------------------*/
extern char * prog;
/*-----------------------------------------*/
struct source_node{
char * name;
};
struct target_node{
char * name;
struct target_node * next;
struct source_node * src_node;
};
struct target_node * first = NULL;
/*-----------------------------------------------------*/
/* return 1 if name is in the target linked list 0 otherwise */
bool is_target(char * name);
/* returns a new target_node */
struct target_node * new_target_node(char * name);
/* insert a new target_node into the list */
void insert_target_node(char * name);
/* remove a target_node from the list */
void remove_target_node(char * name);
/* print the current linked list */
void print_target_list(int opts);
#endif
任何帮助将appricated
在target.c文件的头文件或外部文件中使它外接会更好吗?什么会更有意义/共同的地方 – 2012-04-18 01:22:37
@Greg:在标题中设置为'extern' - 对象的所有用户都需要获取'extern'声明,以便它们不定义它。只有对象的“所有者”才能定义/初始化它。 – 2012-04-18 01:32:29
@MichaelBurr好的谢谢 – 2012-04-18 01:36:07