《unix环境高级编程》的出错处理函数(fun1.c)

#include "apue.h" #include <errno.h> /*for definition of errno*/ #include <stdarg.h> /*ISO C varialbe aruments*/ static void err_doit(int,int,const char*,va_list); /* *Nonfatal error related to a system call. *Print a message and return */ void err_ret(const char *fmt, ...) { va_list ap; va_start(ap,fmt); err_doit(1,errno,fmt,ap); va_end(ap); } /* *Fatal error related to a system call *Print a message and terminate. */ void err_sys(const char *fmt, ...) { va_list ap; err_doit(1,errno,fmt,ap); va_end(ap); exit(1); } /* *Fatal error unrelated to a system call. *Error code passed as explict parameter *Print a message and terminate */ void err_exit(int error,const char *fmt, ...) { va_list ap; va_start(ap,fmt); err_doit(1,error,fmt,ap); va_end(ap); exit(1); } /* *Fatal error related to a system call. *Print a message,dump core,and terminate. */ void err_dump(const char *fmt, ...) { va_list ap; va_start(ap,fmt); err_doit(1,errno,fmt,ap); va_end(ap); abort(); /*dump core and terminate*/ exit(1); /*shouldn't get here*/ } /* *Nonfatal error unrelated to a system call. *Pirnt a message and return */ void err_msg(const char *fmt, ...) { va_list ap; va_start(ap,fmt); err_doit(0,0,fmt,ap); va_end(ap); } /* *Fatal error unrelated to a system call *Print a message and terminate */ void err_quit(const char *fmt, ...) { va_list ap; va_start(ap,fmt); err_doit(0,0,fmt,ap); va_end(ap); exit(1); } /* *Print a message and return to caller *Caller specifies "errnoflag" */ 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); /*in case stdout and stderr are the same*/ fputs(buf,stderr); fflush(NULL); /*flushes all stdio output streams*/ }