C++/Php/Python/Shell 程序按行读取文件或者控制台

 1 #include<stdio.h>
 2 #include<string.h>
 3 
 4 int main(){
 5     const char* in_file = "input_file_name";
 6     const char* out_file = "output_file_name";
 7 
 8     FILE *p_in = fopen(in_file, "r");
 9     if(!p_in){
10         printf("open file %s failed!!!", in_file);
11         return -1;
12     }
13         
14     FILE *p_out = fopen(out_file, "w");
15     if(!p_in){
16         printf("open file %s failed!!!", out_file);
17         if(!p_in){
18             fclose(p_in);
19         }
20         return -1;
21     }
22 
23     char buf[2048];
24     //按行读取文件内容
25     while(fgets(buf, sizeof(buf), p_in) != NULL) {
26         //写入到文件
27         fwrite(buf, sizeof(char), strlen(buf), p_out);
28     }
29 
30     fclose(p_in);
31     fclose(p_out);
32     return 0;
33 }

 1 #include<stdio.h>
 2 
 3 int main(){
 4     char buf[2048];
 5 
 6     gets(buf);
 7     printf("%s\n", buf);
 8 
 9     return 0;
10 }
11 
12 /// scanf 遇到空格等字符会结束
13 /// gets 遇到换行符结束

 1 <?php
 2 $filename = "input_file_name";
 3 
 4 $fp = fopen($filename, "r");
 5 if(!$fp){
 6     echo "open file $filename failed\n";
 7     exit(1);
 8 }
 9 else{
10     while(!feof($fp)){
11         //fgets(file,length) 不指定长度默认为1024字节
12         $buf = fgets($fp);
13 
14         $buf = trim($buf);
15         if(empty($buf)){
16             continue;
17         }
18         else{
19             echo $buf."\n";
20         }
21     }
22     fclose($fp);
23 }
24 ?>

 1 <?php
 2 $fp = fopen("/dev/stdin", "r");
 3 
 4 while($input = fgets($fp, 10000)){
 5         $input = trim($input);
 6        echo $input."\n";
 7 }
 8 
 9 fclose($fp);
10 ?>

 1 #coding=utf-8
 2 
 3 # 如果要在python2的py文件里面写中文，则必须要添加一行声明文件编码的注释，否则python2会默认使用ASCII编码。
 4 # 编码申明，写在第一行就好 
 5 import sys
 6 
 7 input = sys.stdin
 8 
 9 for i in input:
10     #i表示当前的输入行
11 
12     i = i.strip()
13     print i
14 
15 input.close()

1 #!/bin/bash
2 
3 #读取文件, 则直接使用文件名; 读取控制台, 则使用/dev/stdin
4 
5 while read line
6 do
7     echo ${line}
8 done < filename

1 #!/bin/bash
2 
3 while read line
4 do
5     echo ${line}
6 done < /dev/stdin