打印从包含特定单词的文件中读取的行

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()

{
  int i, p=0;;
    int c;
    char file_name[100];
    char  search[10];

    printf("Enter the file name:");
    scanf("%s", file_name);
    printf("Search word:");
    scanf("%s", search);

    FILE *f = fopen((strcat(file_name, ".txt")), "rb");
    fseek(f, 0, SEEK_END);
    long pos = ftell(f); 
    fseek(f, 0, SEEK_SET);

    char *bytes = malloc(pos + 1);
    fread(bytes, pos, 1, f);
    bytes[ pos ] = '
 
 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()

{
  int i, p=0;;
    int c;
    char file_name[100];
    char  search[10];

    printf("Enter the file name:");
    scanf("%s", file_name);
    printf("Search word:");
    scanf("%s", search);

    FILE *f = fopen((strcat(file_name, ".txt")), "rb");
    fseek(f, 0, SEEK_END);
    long pos = ftell(f); 
    fseek(f, 0, SEEK_SET);

    char *bytes = malloc(pos + 1);
    fread(bytes, pos, 1, f);
    bytes[ pos ] = '\0'; 

/*search*/

    if (strstr(bytes, search) != NULL){
        printf("found\n");
        p = 1;}
    else{
        printf("Not found\n");

        p=0;}

    free(bytes);

   char *found = strstr( bytes, search );
   if ( found != NULL )
   {
    char *lineStart;
    for(lineStart = strchr(bytes, '\n');  !strcmp(lineStart,"\n"); 
        lineStart = strchr(lineStart+1, '\n')){
      printf("%s\n", lineStart);  
   }
  }
}
 
 
The above stated code is supposed to search for a word in a file (.txt) and if found it should print "found" and print the line it was found in. For example, if searched for a word "Brick" in the file, and if found in a sentence like "The house is made of red bricks", then it prints the whole sentence as the output i.e "The house is made of the red bricks". 
 
 
上面提到的代码应该在文件(.txt)中搜索一个单词,如果找到它应该打印“找到”并打印它找到的行。例如,如果在文件中搜索单词“Brick”如果在“房子是用红砖砌成的”这样的句子中找到,那么它打印整个句子作为输出,即“房子是由红砖砌成的”。
 
 
I am having trouble printing the line containing the search word. I am trying to use pointer to move to the start of the current line and then navigate incrementally but I am kinda stuck in how to make the pointer stop at the end of the line and just print up till that point.
 
  
  
 
我在打印包含搜索词的行时遇到问题。我试图使用指针移动到当前行的开头,然后逐步导航,但我有点陷入如何使指针停在行的末尾,只是打印到那一点。
 
 
1 个解决方案
 
 
 
  
#1
 
  
 
  
 
   
 
   
The issue with your code is, you call free(bytes); inside your code and after that, you continue to use bytes. This invokes undefined behavior.
 
   
您的代码的问题是,您调用free(bytes);在你的代码中,然后继续使用字节。这会调用未定义的行为。
 
   
Also, i'll suggest
 
   
另外,我建议
 
   
 
    
change your scanf() instruction
更改scanf()指令
 
scanf("%s", file_name);
 
and
 
scanf("%s", search);
 
to
 
scanf("99%s", file_name);
 
and
 
scanf("9%s", search);
 
to avoid the risk of buffer overflow.
避免缓冲区溢出的风险。
 
    
Always check for the success of fopen() before using the returned pointer.
在使用返回的指针之前,请务必检查fopen()是否成功。
 
   
 
   
However, from the logical point, i'll suggest you
 
   
但是,从逻辑上看,我会建议你
 
   
 
    
Read a whole line by line from the file using fgets()
 
    
使用fgets()从文件中逐行读取一行
 
    
Search for the particular word using strstr().
 
    
使用strstr()搜索特定单词。
 
    
If found, print the whole line, otherwise, continue to step 1 until fgets() return NULL.
 
    
如果找到,则打印整行,否则,继续执行步骤1,直到fgets()返回NULL。
 
   
 
   
Notes:
 
   
 
    
the recommended signature of main() is int main(void).
 
    
main()的推荐签名是int main(void)。
 
    
Always initialize all local variables.
 
    
始终初始化所有局部变量。
 
   
 
  
 
 
 

'; 

/*search*/

    if (strstr(bytes, search) != NULL){
        printf("found\n");
        p = 1;}
    else{
        printf("Not found\n");

        p=0;}

    free(bytes);

   char *found = strstr( bytes, search );
   if ( found != NULL )
   {
    char *lineStart;
    for(lineStart = strchr(bytes, '\n');  !strcmp(lineStart,"\n"); 
        lineStart = strchr(lineStart+1, '\n')){
      printf("%s\n", lineStart);  
   }
  }
}
#include <stdio.h>
#include <stdlib.h>
#include