c - Reverse characters word in array -

for exemple need invers "paris" "sirap"...

my main:

int main(void) {     char w1[] = "paris";     reverseword(w1);     printf("the new word is: %s",w1);     return0; } 

and function:

void reverseword(char *str) {      int counter=0;      for(int i=0; *(str+i)!='\0'; i++)           counter++;       int length = counter-1;       char temp[length];       for(int j=0; temp[j]=='\0'; j++)           temp[j]=str[length-j]; } 

now have renverse word in temp[]. need put in pointer *str. how can it??

thanks

if want use temp must function this

void reverseword(char *str) {     int i,j;      if(str)     {       int length=strlen(str);       char temp[length+1];        for( j=0; j<length; j++)           temp[j]=str[length-1-j];        temp[j]='\0';        strcpy(str,temp);    }  } 

without using temp follows

void reverseword(char *str) {     int end= strlen(str)-1;     int start = 0;      while( start<end )     {         str[start] ^= str[end];         str[end] ^= str[start];         str[start]^= str[end];          ++start;         --end;     } }