apue.h是作者自己写的一个文件，包含了常用的头文件，系统不自带。其中包含了常用的头文件，以及出错处理函数的定义。使用起来确实很方便。
使用apue.h需要一些配置（仅linux、unix可以使用）
首先下载对应版本的压缩包
选择版本
新建一个自己准备存放源码的目录，然后下载
mkdir APUE
cd APUE
wget http://www.apuebook.com/src.tar.gz
tar -zxvf src.tar.gz
解压后的文件在目录"aupe.3e"下。
apue.h内容如下：
#ifndef _APUE_H
#define _APUE_H
#define _XOPEN_SOURCE 600 /* Single UNIX Specification, Version 3 */
#include /* some systems still require this */
#include
#include /* for winsize */
#ifndef TIOCGWINSZ
#include
#endif
#include /* for convenience */
#include /* for convenience */
#include /* for offsetof */
#include /* for convenience */
#include /* for convenience */
#include /* for SIG_ERR */
#define MAXLINE 4096 /* max line length */
/*
* Default file access permissions for new files.
*/
#define FILE_MODE (S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH)
/*
* Default permissions for new directories.
*/
#define DIR_MODE (FILE_MODE | S_IXUSR | S_IXGRP | S_IXOTH)
typedef void Sigfunc(int); /* for signal handlers */
#if defined(SIG_IGN) && !defined(SIG_ERR)
#define SIG_ERR ((Sigfunc *)-1)
#endif
#define min(a,b) ((a) < (b) ? (a) : (b))
#define max(a,b) ((a) > (b) ? (a) : (b))
/*
* Prototypes for our own functions.
*/
char *path_alloc(int *); /* Figure 2.15 */
long open_max(void); /* Figure 2.16 */
void clr_fl(int, int); /* Figure 3.11 */
void set_fl(int, int); /* Figure 3.11 */
void pr_exit(int); /* Figure 8.5 */
void pr_mask(const char *); /* Figure 10.14 */
Sigfunc *signal_intr(int, Sigfunc *); /* Figure 10.19 */
int tty_cbreak(int); /* Figure 18.20 */
int tty_raw(int); /* Figure 18.20 */
int tty_reset(int); /* Figure 18.20 */
void tty_atexit(void); /* Figure 18.20 */
#ifdef ECHO /* only if has been included */
struct termios *tty_termios(void); /* Figure 18.20 */
#endif
void sleep_us(unsigned int); /* Exercise 14.6 */
ssize_t readn(int, void *, size_t); /* Figure 14.29 */
ssize_t writen(int, const void *, size_t); /* Figure 14.29 */
void daemonize(const char *); /* Figure 13.1 */
int s_pipe(int *); /* Figures 17.6 and 17.13 */
int recv_fd(int, ssize_t (*func)(int,
const void *, size_t));/* Figures 17.21 and 17.23 */
int send_fd(int, int); /* Figures 17.20 and 17.22 */
int send_err(int, int,
const char *); /* Figure 17.19 */
int serv_listen(const char *); /* Figures 17.10 and 17.15 */
int serv_accept(int, uid_t *); /* Figures 17.11 and 17.16 */
int cli_conn(const char *); /* Figures 17.12 and 17.17 */
int buf_args(char *, int (*func)(int,
char **)); /* Figure 17.32 */
int ptym_open(char *, int); /* Figures 19.8, 19.9, and 19.10 */
int ptys_open(char *); /* Figures 19.8, 19.9, and 19.10 */
#ifdef TIOCGWINSZ
pid_t pty_fork(int *, char *, int, const struct termios *,
const struct winsize *); /* Figure 19.11 */
#endif
int lock_reg(int, int, int, off_t, int, off_t); /* Figure 14.5 */
#define read_lock(fd, offset, whence, len) \
lock_reg((fd), F_SETLK, F_RDLCK, (offset), (whence), (len))
#define readw_lock(fd, offset, whence, len) \
lock_reg((fd), F_SETLKW, F_RDLCK, (offset), (whence), (len))
#define write_lock(fd, offset, whence, len) \
lock_reg((fd), F_SETLK, F_WRLCK, (offset), (whence), (len))
#define writew_lock(fd, offset, whence, len) \
lock_reg((fd), F_SETLKW, F_WRLCK, (offset), (whence), (len))
#define un_lock(fd, offset, whence, len) \
lock_reg((fd), F_SETLK, F_UNLCK, (offset), (whence), (len))
pid_t lock_test(int, int, off_t, int, off_t); /* Figure 14.6 */
#define is_read_lockable(fd, offset, whence, len) \
(lock_test((fd), F_RDLCK, (offset), (whence), (len)) == 0)
#define is_write_lockable(fd, offset, whence, len) \
(lock_test((fd), F_WRLCK, (offset), (whence), (len)) == 0)
void err_dump(const char *, ...); /* Appendix B */
void err_msg(const char *, ...);
void err_quit(const char *, ...);
void err_exit(int, const char *, ...);
void err_ret(const char *, ...);
void err_sys(const char *, ...);
void log_msg(const char *, ...); /* Appendix B */
void log_open(const char *, int, int);
void log_quit(const char *, ...);
void log_ret(const char *, ...);
void log_sys(const char *, ...);
void TELL_WAIT(void); /* parent/child from Section 8.9 */
void TELL_PARENT(pid_t);
void TELL_CHILD(pid_t);
void WAIT_PARENT(void);
void WAIT_CHILD(void);
#endif /* _APUE_H */
作者使用的是BSD，而我们主要运行在Linux上，准确的说是CentOS上，所以需要对源文件进行一点调整
把文件拷入/usr/inlcude/目录下
cd ./src.3e/apue.3e
cp ./include/apue.h /usr/include/
cp ./lib/error.c /usr/include/
编辑"/usr/include/apue.h"
vim /usr/include/apue.h
光标移动到文件最后一行"#endif"的前面，然后添加如下代码
#include "error.c"
安装BSD开发SDK(CentOS)
yum install libbsd
yum install libbsd-devel
Ubuntu用apt-get就行
sudo apt-get install libbsd-dev
编译
进入apue.3e目录下
make
编译好就可以用了
#include "apue.3e/include/apue.h"