爲什麼編譯器不能找到mysql包含？

每當我嘗試編譯一個文件與MySQL包括我得到的錯誤，'未定義的參考'的所有調用我的mysql。我的包裝中有圖書館，我相信我會按照我應有的方式包括它。我不知道到底發生了什麼。爲什麼編譯器不能找到mysql包含？

下面是測試文件，我想：

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


int main(void) { 
    MYSQL *conn; 
    MYSQL_RES *res; 
    MYSQL_ROW row; 
    char *server = "localhost"; 
    char *user = "????"; 
    char *pass = "????"; 
    char *db = "TEST_DB"; 

    conn = mysql_init(NULL); 

    if(!mysql_real_connect(conn, server, user, pass, db, 0, NULL, 0)) 
     fprintf(stderr, "%s\n", mysql_error(conn)); 
    if(!mysql_query(conn, "show tables")) 
     fprintf(stderr, "%s\n", mysql_error(conn)); 

    res = mysql_use_result(conn); 
    printf("MySQL Tables in mysql DB: \n"); 

    while((row = mysql_fetch_row(res)) != NULL) 
     printf("%s \n", row[0]); 

    mysql_free_result(res); 
    mysql_close(conn); 
    return 0; 
}

下面是簡單的編譯器命令我想，以及操作的輸出：

clang test.c -o driver

鐺輸出：

clang version 3.6.0 (tags/RELEASE_360/final) 
Target: x86_64-unknown-linux-gnu 
Thread model: posix 
Found candidate GCC installation: /usr/bin/../lib/gcc/x86_64-unknown-linux-gnu/4.9.2 
Found candidate GCC installation: /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2 
Found candidate GCC installation: /usr/lib/gcc/x86_64-unknown-linux-gnu/4.9.2 
Found candidate GCC installation: /usr/lib64/gcc/x86_64-unknown-linux-gnu/4.9.2 
Selected GCC installation: /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2 
Candidate multilib: .;@m64 
Selected multilib: .;@m64 

"/usr/bin/ld" --eh-frame-hdr -m elf_x86_64 -dynamic-linker /lib64/ld-linux-x86-64.so.2 -o driver /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../lib64/crt1.o /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../lib64/crti.o /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/crtbegin.o -L/usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2 -L/usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../lib64 -L/usr/bin/../lib64 -L/lib/../lib64 -L/usr/lib/../lib64 -L/usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/../../.. -L/usr/bin/../lib -L/lib -L/usr/lib /tmp/ellipsis/test-47b79a.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/crtend.o /usr/bin/../lib64/gcc/x86_64-unknown-linux-gnu/4.9.2/../../../../lib64/crtn.o 

/tmp/ellipsis/test-47b79a.o: In function `main': 
test.c:(.text+0x4f): undefined reference to `mysql_init' 
test.c:(.text+0x8d): undefined reference to `mysql_real_connect' 
test.c:(.text+0xb1): undefined reference to `mysql_error' 
test.c:(.text+0xdf): undefined reference to `mysql_query' 
test.c:(.text+0x102): undefined reference to `mysql_error' 
test.c:(.text+0x126): undefined reference to `mysql_use_result' 
test.c:(.text+0x147): undefined reference to `mysql_fetch_row' 
test.c:(.text+0x180): undefined reference to `mysql_free_result' 
test.c:(.text+0x189): undefined reference to `mysql_close' 
clang: error: linker command failed with exit code 1 (use -v to see invocation)

而c mysql庫存在'/ usr/include/mysql /'中

來源

2015-04-03 nacy

試試clang test.c -o driver -lmysqlclient也許？ #include指令僅供編譯器知道該庫是如何使用的。您需要在編譯中包含二進制文件。

來源

2015-04-03 23:46:00 mathieu

真棒，那工作..它究竟做了什麼？你知道爲什麼沒有這個說法，它不工作？ – nacy 2015-04-03 23:47:41

我按照你的要求編輯我的答案^^編譯器需要知道「如何」（使用函數;這是#include），鏈接器需要知道「where」（真正的函數;即-l）。 – mathieu 2015-04-03 23:49:35

正確。謝謝。 – nacy 2015-04-03 23:53:53

爲什麼編譯器不能找到mysql包含？

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