String Manipulations

Problem: Reverses a character string in place.
Solution:read

#include <iostream>
using namespace std;

char *revstr(char * str);

/**
 ******************************************************************************
 *
 * Reverses character string in place
 * 
 ******************************************************************************
 */
int main (int argc, char *argv[])
{
    char buf[128];
    char *str = buf;
    
    cout << "Enter string:";
    str = fgets(buf, 127, stdin);

    if (str)
    {
        size_t len = strlen(str) -1;    // subtract line feed
        str[len] = '\0';                // strip line feed
        printf("in (%03d): %s\n", len, str);
        printf("out(%03d): %s\n", len, revstr(str));
    }
    return(0);
}


/**
 ******************************************************************************
 *
 * Reverses character string in place
 * 
 * @param str 
 * 
 * @return char* 
 *
 ******************************************************************************
 */
char *revstr(char *str)
{
    if ( (str!=NULL) && (*str!='\0') )
    {
        size_t len = strlen(str);

        char *start, *end;
        start = str;
        end = &str[len-1];  // adjust index to zero base
        for(size_t i=0; i<len/2; i++)
        {
            *start ^= *end;
            *end   ^= *start;
            *start++ ^= *end--;
        }
    }
    return str;
}
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