C Source code for reversing words in a string.

bool reverseWords( char str[] ){
char *buffer;
int tokenReadPos, wordReadPos, wordEnd, writePos = 0;

/* Position of the last character is length - 1 */
tokenReadPos = strlen(str) - 1;

buffer = (char *) malloc(tokenReadPos + 2);
if( !buffer )
return false; /* reverseWords failed */

while( tokenReadPos >= 0 ){

if( str[tokenReadPos] == ' ' ){ /* Non-word characters */
/* Write character */
buffer[writePos++] = str[tokenReadPos--];

} else { /* Word characters */
/* Store position of end of word */
wordEnd = tokenReadPos;

/* Scan to next non-word character */
while( tokenReadPos >= 0 && str[tokenReadPos] != ' ' )
tokenReadPos--;

/* tokenReadPos went past the start of the word */
wordReadPos = tokenReadPos + 1;

/* Copy the characters of the word */
while( wordReadPos <= wordEnd ){
buffer[writePos++] = str[wordReadPos++];
}
}
}
/* null terminate buffer and copy over str */
buffer[writePos] = '\0';
strcpy(str, buffer);

free(buffer);

return true; /* ReverseWords successful */
}