Re: There is a problem when I compile the case with -lcrypt

[Andreas Schwab <schwab at linux-m68k dot org>]

Cui Bixuan <cuibixuan@huawei.com> writes:

> int main() {
>         char *c, *s;
>         long int i;
>
>         s="9223372036854775807";
>         strtol(s, &c, 0);
>
>         printf("errno=%d\n",errno);
>
>         return 0;
> }
>
> Then I compile and run it in arm64 system:
>
> aarch64-linux-gnu-gcc test.c -o test
> aarch64-linux-gnu-gcc test.c -o test-1 -lcrypt
>
> ./test
> errno=0
>
> ./test-1
> errno=2
>
> I don't know why? Is this a problem?

The value of errno is unspecified except after a function call that is
documented to set errno _and_ that function call returned a failure
condition.  Additionally, some functions like strtol are documented to
not modify errno if they return sucessfully.  If you want to check for
failure for such a function you need to set errno to zero before the
call.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."