【入門】C程序設計（第三版）譚浩強—第十二至十四章

 第十二至十四章要點整理圖：

 

第十三章例題：

例題13.1
#include<stdio.h>
#include<stdlib.h>
void main()
{
    FILE *fp;
    char ch,filename[10];
    scanf("%s",filename);   /*輸入文件名*/
    if((fp=fopen(filename,"w"))==NULL)  /*爲輸出打開一個文件*/
    {
        printf("cannot open file\n");
        exit(0);    /*終止程序*/
    }
    ch=getchar();   /*此語句用來接收在執行scanf語句時最後輸入的回車符*/
    ch=getchar();   /*接收輸入的第一個字符*/
    while(ch!='#')
    {
        fputc(ch,fp);   /*把字符寫到磁盤文件上去*/
        putchar(ch);    /*終端顯示*/
        ch=getchar();
    }
    putchar(10);
    fclose(fp);
}

例題13.2
#include<stdio.h>
#include<stdlib.h>
void main()
{
    FILE *in,*out;
    char ch,infile[15],outfile[15];     /*注意數組長度，在輸入文件名時*/
    printf("Enter the infile name:\n");
    scanf("%s",infile);
    printf("Enter the outfile name:\n");
    scanf("%s",outfile);
    if((in=fopen(infile,"r"))==NULL)
    {
        printf("cannot open infile\n");
        exit(0);
    }
    if((out=fopen(outfile,"w"))==NULL)
    {
        printf("cannot open outfile\n");
        exit(0);
    }
    while(!(feof(in)))
    {
        fputc(fgetc(in),out);
    }
    fclose(out);
    fclose(in);
}

#include<stdio.h>
#include<stdlib.h>
void main(int argc,char *argv[])
{
    FILE *in,*out;
    char ch;
    if(argc!=3)
    {
        printf("You forgot to enter a filename\n");
        exit(0);
    }
    if((in=fopen(argv[1],"r"))==NULL)
    {
        printf("cannot open infile\n");
        exit(0);
    }
    if((out=fopen(argv[2],"w"))==NULL)
    {
        printf("cannot open outfile\n");
        exit(0);
    }
    while(!feof(in))
    {
        fputc(fgetc(in),out);
    }
    fclose(in);
    fclose(out);
}