warning: statement has no effect [-Wunused-value]

Using Arduino Programming Questions
1

While working on a library I used the 'strcpy' function within a method.

strcmp(pBuff, "Unknown");

When it compiles I get the warning message:
warning: statement has no effect [-Wunused-value]

I have no idea how a function call to a standard library function can have no effect.

I also tried the statement:

strcmp_P(pBuff, (PGM_P) F("Unknown"));

This compiles without error but does not work (i.e. buffer remains unchanged).

2

That's strcmp you have there, not strcpy... Compare two strings and throw away the result...?

3

If you want to copy a string, you probably shouldnt use strcmp() to do it.

4

DAH