www.pudn.com > 文件恢复及修补 C 语言源程序.zip > FGETS.C

 
/* Copyright (C) 1981,1982 by Manx Software Systems and Thomas Fenwick */ 
#include "stdio.h" 
 
char *gets(line) 
char *line; 
{ 
        register char *cp; 
        register int i; 
 
        cp = line; 
        while ((i = getchar()) != EOF && i != '\n') 
                *cp++ = i; 
        *cp = 0; 
        if (i == EOF && cp == line) 
                return NULL; 
        return line; 
} 
 
char *fgets(s, n, fp) 
char *s; FILE *fp; 
{ 
        register c; 
        register char *cp; 
 
        cp = s; 
        while (--n > 0 && (c = agetc(fp)) != EOF) { 
                *cp++ = c; 
                if (c == '\n') 
                        break; 
        } 
        *cp = 0; 
        if (c == EOF && cp == s) 
                return NULL; 
        return(s); 
} 
 
agetc(ptr) 
register FILE *ptr; 
{ 
        register int c; 
 
top: 
        if ((c = getc(ptr)) != EOF) { 
                switch (c &= 127) { 
                case 0x1a: 
                        --ptr->_bp; 
                        return EOF; 
                case '\r': 
                case 0: 
                        goto top; 
                } 
        } 
        return c; 
}