编译Unix环境高级编程一书中的代码出错

kiron

以下是ls.c的代码

1. #include <sys/types.h>
   
2. #include <dirent.h>
   
3. /* #include "ourhdr.h" */
   
4. 
   
5. int
   
6. main (int argc, char *argv[]) {
   
7. DIR *dp;
   
8. struct dirent *dirp;
   
9. if (argc != 2)
   
10. err_quit("a single argument (the directory name) is required");
    
11. if (( dp = opendir (argv[1])) == 0)
    
12. err_sys("can't open %s",argv[1]);
    
13. 
    
14. while ( (dirp =readdir(dp)) != 0)
    
15. printf("%s\n",dirp->d_name);
    
16. 
    
17. closedir(dp);
    
18. exit(0);
    
19. }

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头文件ourhdr.h是自定义的，内容如下：

1. /* Our own header, to be included *after* all standard system headers */
   
2. 
   
3. #ifndef __ourhdr_h
   
4. #define __ourhdr_h
   
5. 
   
6. #include <sys/types.h> /* required for some of our prototypes */
   
7. #include <stdio.h>     /* for convenience */
   
8. #include <stdlib.h>    /* for convenience */
   
9. #include <string.h>    /* for convenience */
   
10. #include <unistd.h>    /* for convenience */
    
11. 
    
12. #define MAXLINE 4096  /* max line length */
    
13. 
    
14. #define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)
    
15. /* default file access permissions for new files */
    
16. 
    
17. #define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH)
    
18. /* default permissions for new directories */
    
19. 
    
20. typedef void Sigfunc(int);    /* for signal handlers */
    
21. /* 4.3BSD Reno <signal.h> doesn't define SIG_ERR */
    
22. 
    
23. #if defined(SIG_IGN) && !DEFINED(SIG_ERR)
    
24. #define SIG_ERR ((Sigfunc *) -1)
    
25. #endif
    
26. 
    
27. #define min(a,b) ((a) < (b) ? (a) : (b))
    
28. #define max(a,b) ((a) > (b) ? (a) : (b))
    
29. 
    
30. /* prototypes for our own functions */
    
31. char *path_alloc(int *);    /* Program 2.2 */
    
32. int open_max(void);         /* Program 2.3 */
    
33. void clr_fl(int, int);      /* Program 3.5 */
    
34. void set_fl(int, int);      /* Program 3.5 */
    
35. void pr_exit(int);          /* Program 8.3 */
    
36. void pr_mask(const char *); /* Program 10.10 */
    
37. Sigfunc *signal_intr(int, Sigfunc *); /* Program 10.13 */
    
38. 
    
39. int tty_cbreak(int);        /* Program 11.10 */
    
40. int tty_raw(int);           /* Program 11.10 */
    
41. int tty_reset(int);         /* Program 11.10 */
    
42. int tty_atexit(int);        /* program 11.10 */
    
43. #ifdef ECHO                         /* only if <termios.h> has been included */
    
44. struct termios *tty_termios(void); /* Program 11.10 */
    
45. #endif
    
46. 
    
47. void sleep_us(unsigned int);        /* Exercise 12.6 */
    
48. ssize_t readn(int, void *, size_t); /* Program 12.13 */
    
49. ssize_t writen(int, const void *,size_t); /* Program 12.12 */
    
50. int daemon_init(void);                /* Programs 13.1 */
    
51. int s_pipe(int *);                /* Programs 15.2  and 15.3 */
    
52. int recv_fd(int, ssize_t (*func)(int, const void *, size_t));
    
53. /* Program 15.6 and 15.8 */
    
54. int send_fd(int, int);                /* Programs 15.5 and 15.7 */
    
55. int send_err(int, int, const char *) /* Programs 15.20 */
    
56. int serv_listen(const char *); /* Programs 15.19 and 15.22 */
    
57. int serv_accept(int, uid_t *);        /* Programs 15.20 and 15.24 */
    
58. int cli_conn(const char *);        /* Programs 15.21 and 15.23 */
    
59. int buf_args(char *, int (*func)(int,char **));        /* Program 15.17 */
    
60. 
    
61. int ptym_open(char *);                /* Programs 19.1 and 19.2 */
    
62. int ptys_open(int, char *);        /* Programs 19.1 ans 19.2 */
    
63. #ifdef TIOCGWINSZ
    
64. pid_z pty_fork(int *, char *, const struct termios *, const struct winsize *);
    
65. /* Program 19.3 */
    
66. #endif
    
67. 
    
68. int lock_fork(int, int, int, off_t, int, off_t); /* Programs 12.2 */
    
69. #define read_lock(fd, offset, whence, len) \
    
70. lock_reg(fd, F_SETLK, F_RDLCK, offset, whence, len)
    
71. #define readw_lock(fd, offset, whence, len) \
    
72. lock_reg(fd, F_SETLKW, F_RDLCK, offset, whence, len)
    
73. #define write_lock(fd, offset, whence, len) \
    
74. lock_reg(fd, F_SETLK, F_WRLCK, offset, whence, len)
    
75. #define writew_lock(fd, offset, whence, len) \
    
76. lock_reg(fd, F_SETLKW, F_WRLCK, offset, whence, len)
    
77. #define un_lock(fd, offset, whence, len) \
    
78. lock_reg(fd, F_SETLK, F_UNLCK, offset, whence, len)
    
79. 
    
80. pid_t lock_test(int, int, off_t, int, off_t); /* Program 12.3 */
    
81. 
    
82. #define is_readlock(fd, offset, whence, len) \
    
83. lock_test(fd, F_RDLCK, offset, whence, len)
    
84. #define is_writelock(fd, offset, whence, len) \
    
85. lock_test(fd, F_WRLCK, offset, whence, len)
    
86. 
    
87. void err_dump(const char *, ...); /* Appendix B */
    
88. void err_msg(const char *, ...);
    
89. void err_quit(const char *, ...);
    
90. void err_ret(const char *, ...);
    
91. void err_sys(const char *, ...);
    
92. 
    
93. void log_msg(const char *, ...); /* Appendix B */
    
94. void log_open(const char *, int, int);
    
95. void log_quit(const char *, ...);
    
96. void log_ret(const char *, ...);
    
97. void log_sys(const char *, ...);
    
98. 
    
99. void TELL_WAIT(void);                /* parent/child form Section 8.8 */
    
100. void TELL_PARENT(pid_t);
     
101. void TELL_CHILD(pid_t);
     
102. void WAIT_PARENT(void);
     
103. void WAIT_CHILD(void);
     
104. 
     
105. #endif /* __ourhdr_h */

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使用下面的命令编译ls.c文件：
gcc -o ls ls.c -I/root/program
其中/root/program目录下有ourhdr.h文件
出错信息如下：

1. cd /root/program/
   
2. gcc -o ls ls.c -I/root/program
   
3. /tmp/ccCUiKUZ.o: In function `main':
   
4. /tmp/ccCUiKUZ.o(.text+0x1f): undefined reference to `err_quit'
   
5. /tmp/ccCUiKUZ.o(.text+0x53): undefined reference to `err_sys'
   
6. collect2: ld returned 1 exit status
   
7. 
   
8. Compilation exited abnormally with code 1 at Thu Jul 15 10:59:25

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是哪出了问题，请指教:thank

kj501

看看这一句，你不是把头文件已经注释掉了吗？

1. 
   
2. /* #include "ourhdr.h" */
   

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doubleelec

undefined reference to `err_quit'
找不到函数的实现,楼主给的源码还少了另一个.c文件

不如不用err_quit和err_sys, 改成直接printf然后exit,试起来方便些

kiron

最初由 kj501 发表
看看这一句，你不是把头文件已经注释掉了吗？

1. 
   
2. /* #include "ourhdr.h" */
   

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sorry,刚学emacs不久，有些热键不熟搞混了

我去掉注释后还是不行，出错如下：

1. cd /root/program/
   
2. gcc -o ls ls.c -I/root/program
   
3. /tmp/ccCOLn3d.o: In function `main':
   
4. /tmp/ccCOLn3d.o(.text+0x1f): undefined reference to `err_quit'
   
5. /tmp/ccCOLn3d.o(.text+0x53): undefined reference to `err_sys'
   
6. collect2: ld returned 1 exit status
   
7. 
   
8. Compilation exited abnormally with code 1 at Thu Jul 15 13:41:46

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doubleelec

/tmp/ccCOLn3d.o(.text+0x1f): undefined reference to `err_quit'
/tmp/ccCOLn3d.o(.text+0x53): undefined reference to `err_sys'
把这两个函数的实现代码加到你的程序中去,或者不要用这两个函数了

kiron

最初由 doubleelec 发表
/tmp/ccCOLn3d.o(.text+0x1f): undefined reference to `err_quit'
/tmp/ccCOLn3d.o(.text+0x53): undefined reference to `err_sys'
把这两个函数的实现代码加到你的程序中去,或者不要用这两个函数了

thanks,我想是还有一个头文件没包含吧，让我再看看，多谢

kj501

是没有链接库文件。这些文件应该可以到作者的主页上去下载。