error.c

Advanced Programming in the UNIX Environment 의 기본적인 error처리 library. 컴파일 해서 Object파일을 만든 후, 실제 실행파일 컴파일 시 링크시켜 줄 것.

 

#include <errno.h>  /* for definition of errno */
#include <stdarg.h>  /* ANSI C header file */
#include "ourhdr.h"

static void err_doit(int, const char *, va_list);

char *pname = NULL;  /* caller can set this from argv[0] */

/* 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, fmt, ap);
    va_end(ap);
    return;
}

/* Fatal error related to a system call.
 * Print a message and terminate. */

void
err_sys(const char *fmt, ...)
{
    va_list  ap;

    va_start(ap, fmt);
    err_doit(1, 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, fmt, ap);
    va_end(ap);
    abort();  /* dump core and terminate */
    exit(1);  /* shouldn't get here */
}

/* Nonfatal error unrelated to a system call.
 * Print a message and return. */

void
err_msg(const char *fmt, ...)
{
    va_list  ap;

    va_start(ap, fmt);
    err_doit(0, fmt, ap);
    va_end(ap);
    return;
}

/* 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, fmt, ap);
    va_end(ap);
    exit(1);
}

/* Print a message and return to caller.
 * Caller specifies "errnoflag". */

static void
err_doit(int errnoflag, const char *fmt, va_list ap)
{
    int  errno_save;
    char buf[MAXLINE];

    errno_save = errno;  /* value caller might want printed */
    vsprintf(buf, fmt, ap);
    if (errnoflag)
        sprintf(buf+strlen(buf), ": %s", strerror(errno_save));
    strcat(buf, "\n");
    fflush(stdout);  /* in case stdout and stderr are the same */
    fputs(buf, stderr);
    fflush(NULL);  /* flushes all stdio output streams */
    return;
}