[Spiffster]

What does this while loop test for?

char str[80], *p;
p=str;

while(*p) {
blah blah blah…
}

I know its tests to see if *p is true, but how does *p become true?

[Chuckit]

When p doesn't point to the value '\0'.

Remember: As far as control statements are concerned, 0 is always false, anything else is true.

[Angus_D]

I guess in "blah blah blah" it increments p, so it loops down the string character by character until the end, when p points to the last byte in the string. The last byte of a cstring is always 0, and the while loop terminates.