如何使用 strtok() 将包含空格的给定字符串拆分为多个字符串？

Question

I have a file named email.txt, which contains some text. I am trying to split the given string containing spaces into multiple strings. The program I wrote does not split the words into separate lines. It gives me the output of the last word of the file. Here is my code

#include <stdio.h>
#include <string.h>
#define MAXCHAR 1000
int main()
{
    FILE *fp2;    
    char str2[MAXCHAR];
    int line = 0;
    char delim[] = " ";
    int init_size = strlen(str2);
    fp2 = fopen("email.txt","r");
    while( fgets( str2, MAXCHAR, fp2 )) {
        line++;
        // printf(" %s",str2);  
    }
    char *ptr = strtok(str2, delim);
    
    while(ptr != NULL)
    {
        printf("%s\n", ptr);
        ptr = strtok(NULL, delim);
    }       
    
    return 0;
}

Answer 1

You are first looping over all the lines in your file, and then you loop over strtok() returns. This means you only ever tokenize the last line read.

You need to nest those loops -- read a line, tokenize, then read the next line.

while( fgets( str2, MAXCHAR, fp2 )) {
    char * ptr;
    line++;
    //  printf(" %s",str2);
    ptr = strtok(str2, delim);

    while(ptr != NULL)
    {
        printf("%s\n", ptr);
        ptr = strtok(NULL, delim);
    }
}

Answer 2

You could just iterate over all the characters and then output either

• the character you just read or
• if the character is a space, a newline character