在我博客中經常使用的“apue.h”和“err_msg.h”

       在我的Linux/Unix的博客中，經常會時候用“apue.h”和“err_msg.h”，這兩個文件的內容如下：

apue.h

/*
 *	Our own hander, to be included before all 
 *  	standard system headers.
 */

#ifndef __APUE_H
#define __APUE_H

#ifndef _XOPEN_SOURCE
#define _XOPEN_SOURCE 600	/* some system still require this */
#endif

#include <sys/stat.h>
#include <sys/termios.h>	/* for winsize*/
#ifndef TIOCGWINSZ
#include <sys/ioctl.h>
#endif

#include <stdio.h>		/* for convenience */
#include <stdlib.h>		/* for convenience */
#include <stddef.h>		/* for offsetof */
#include <string.h>		/* for convenience */
#include <unistd.h>		/* for convenience */
#include <signal.h>		/* 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 *);
long 	open_max(void);
void	clr_fl(int, int);
void 	set_fl(int, int);
void 	pr_exit(int);
void 	pr_mask(const char *);
Sigfunc * signal_intr(int, Sigfunc *);

int	tty_cbreak(int);
int 	tty_raw(int);
int	tty_reset(int);
int 	tty_atexit(void);
#ifdef ECHO /* only if <termios.h> has been included */	
struct termios * tty_termios(void);
#endif

void 	sleep_us(unsigned int);
ssize_t readn(int, void *, size_t);
ssize_t writen(int ,const void * size_t);
void	daemonize(const char *);

int 	s_pipe(int *);
int	recv_fd
	(
		int, 
		ssize_t (*func) (int, const void *, size_t)
	);
int	send_fd(int, int);
int 	send_err(int, int, const char *);
int	serv_listen(const char *);
int 	serv_accept(int, uid_t *);
int 	cli_conn(const char *);
int 	buf_args(char *, int (*func)(int, char **));
int 	ptym_open(char *, int);
int 	ptys_open(char *);

#ifdef TIOCGWINSZ

pid_t pty_fork(int *, char *, int, const struct termios *, const struct winsize *);

#endif

int lock_reg(int, int, int, off_t, int, off_t);
#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_SETWLK, 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);

#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 *, ...);
void	err_msg(const char *, ...);
void 	err_quit(const char *, ...);
void 	err_exit(const char *, ...);
void 	err_ret(const char *, ...);
void 	err_sys(const char *, ...);

void 	log_msg(const char *, ...);
void	log_open(const char *, ...);
void 	log_quit(const char *, ...);
void 	log_ret(const char *, ...);
void 	log_sys(const char *, ...);

void	TELL_WAIT(void);
void 	TELL_PARENT(pid_t);
void 	TELL_CHILD(pid_t);
void	WAIT_PARENT(void);
void 	WAIT_CHILD(void);

#endif /* __APUE_H */

err_msg.h

#include "apue.h"
#include <errno.h>
#include <stdarg.h>

static void err_doit(int errnoflag, int error, const char * fmt, va_list ap);

void err_ret(const char * fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	err_doit(1, errno, fmt, ap);
	va_end(ap);
}

void err_sys(const char * fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	err_doit(1, errno, fmt, ap);
	va_end(ap);
	exit(1);
}

void err_exit(const char * fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	err_doit(1, errno, fmt, ap);
	va_end(ap);
	exit(1);
}

void err_dump(const char * fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	err_doit(1, errno, fmt, ap);
	va_end(ap);
	abort();
	exit(1);
}

void err_msg(const char * fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	err_doit(0, 0, fmt, ap);
	va_end(ap);
}

void err_quit(const char * fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);	
	err_doit(0, 0, fmt, ap);
	va_end(ap);
	exit(1);
}

static void err_doit(int errnoflag, int error, const char * fmt, va_list ap)
{
	char buf[MAXLINE];
	vsnprintf(buf, MAXLINE, fmt, ap);
	if (errnoflag) 
	{
		snprintf(buf + strlen(buf), MAXLINE - strlen(buf), ": %s", strerror(error));
	}
	strcat(buf, "\n");
	fflush(stdout);
	fputs(buf, stderr);
	fflush(NULL);
}