未定义引用`readline'

Question

我在尝试运行维基百科中提供的GNU Readline库示例代码时遇到问题.在这里:

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <readline/readline.h>
#include <readline/history.h>

int main()
{
    char* input, shell_prompt[100];

    // Configure readline to auto-complete paths when the tab key is hit.
    rl_bind_key('\t', rl_complete);

    for(;;) {
        // Create prompt string from user name and current working directory.
        snprintf(shell_prompt, sizeof(shell_prompt), "%s:%s $ ", getenv("USER"), getcwd(NULL, 1024));

        // Display prompt and read input (n.b. input must be freed after use)...
        input = readline(shell_prompt);

        // Check for EOF.
        if (!input)
            break;

        // Add input to history.
        add_history(input);

        // Do stuff...

        // Free input.
        free(input);
    }
}

我正在创建一个受限制的环境,因为readline不可用,所以我必须下载源代码,编译它并将其安装到我的家庭目录.

这是我的主目录中的结构:

.local
??? include
?   ??? readline
?       ??? chardefs.h
?       ??? history.h
?       ??? keymaps.h
?       ??? readline.h
?       ??? rlconf.h
?       ??? rlstdc.h
?       ??? rltypedefs.h
?       ??? tilde.h
??? lib
    ??? libhistory.a
    ??? libhistory.so -> libhistory.so.6
    ??? libhistory.so.6 -> libhistory.so.6.2
    ??? libhistory.so.6.2
    ??? libreadline.a
    ??? libreadline.so -> libreadline.so.6
    ??? libreadline.so.6 -> libreadline.so.6.2
    ??? libreadline.so.6.2

问题是,当我调用gcc时,它会抛出一个错误:

$ gcc hello.c -o hello_c.o -I /home/my-home-dir/.local/include
/tmp/cckC236E.o: In function `main':
hello.c:(.text+0xa): undefined reference to `rl_complete'
hello.c:(.text+0x14): undefined reference to `rl_bind_key'
hello.c:(.text+0x60): undefined reference to `readline'
hello.c:(.text+0x77): undefined reference to `add_history'
collect2: error: ld returned 1 exit status

有关于这个答案在这里,但我不使用NetBeans,我不太清楚如何指定要在命令行上库的路径.

我试图告诉链接器库的位置,但结果仍然相同:

$ gcc hello.c -o hello_c.o -I /home/my-home-dir/.local/include -Xlinker "-L /home/my-home-dir/.local/lib"
/tmp/cceiePMr.o: In function `main':
hello.c:(.text+0xa): undefined reference to `rl_complete'
hello.c:(.text+0x14): undefined reference to `rl_bind_key'
hello.c:(.text+0x60): undefined reference to `readline'
hello.c:(.text+0x77): undefined reference to `add_history'
collect2: error: ld returned 1 exit status

我在这里可能缺少什么想法？

Answer 1

您需要使用gcc参数中的-lreadline来链接实际库