Segmentation fault in strtok

问题

I keep getting that error. I am pretty sure it has something to do with memory allocation but i'm not quite sure how to fix it.

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

char * VOWELS ="aeiouAEIOU";


void printLatinWord(char *a);


int main(int argc, char **argv){
    char phrase[100];
    char *word = malloc(sizeof(char) *100);

    printf("Enter the phrase to be translated: \n");

    fgets(word, 100, stdin);
    printf("The phrase in Pig Latin is:\n");
    word = strtok(phrase, " ");
    printLatinWord(word);

    return 0;
}

void printLatinWord(char *word){
    while (strchr(VOWELS, *word) == NULL){
    char consonant = *word;
    char *to=word, *from=word+1;

    while (*from)
         *to++=*from++;
         *to=consonant;
    }
    printf("%say\n", word);
}

the out put gives "Segmentation fault (core dumped)"

回答1:

fgets(word, 100, stdin);
word = strtok(phrase, " ");

You have the parameters the wrong way round here. You're splitting the string in phrase which is uninitialized, and then you're assigning the result to word thus overwriting the pointer to the memory you previously allocated.

You probably intended for the fgets to read the input into phrase rather than word.

来源：https://stackoverflow.com/questions/8097074/segmentation-fault-in-strtok