November 02, 2005
I'm able to successfully use strtol() with a well-formed numeric string.  However, I'm unable to retrieve the errno() values specified in the strtol() documentation when I provide a poorly-formed string.  In all cases that I have tried thus far, getErrno() always returns zero:

    char[] s = "QQQ\0";
    setErrno(0);
    int k = strtol(cast(char*)s, null, 0); // base 10
    int errno = getErrno();
    if (errno == 0) {
        writefln("k = %d", k);
    } else {
        writefln("Error : %d", errno);
    }

Any ideas?

Thanks,
Garett


November 02, 2005
On Tue, 1 Nov 2005 20:13:53 -0600, Garett Bass <garettbass@studiotekne.com> wrote:
> I'm able to successfully use strtol() with a well-formed
> numeric string.  However, I'm unable to retrieve the errno()
> values specified in the strtol() documentation when I
> provide a poorly-formed string.  In all cases that I have
> tried thus far, getErrno() always returns zero:
>
>     char[] s = "QQQ\0";
>     setErrno(0);
>     int k = strtol(cast(char*)s, null, 0); // base 10
>     int errno = getErrno();
>     if (errno == 0) {
>         writefln("k = %d", k);
>     } else {
>         writefln("Error : %d", errno);
>     }

I'm not sure it _should_ be setting errno, from MSDN:

"strtol returns 0 if no conversion can be performed. wcstol returns values analogously to strtol. For both functions, errno is set to ERANGE if overflow or underflow occurs."

It only sets errno on overflow or underflow.

I write this to test my theory:

#include <stdlib.h>
#include <stdio.h>

void main()
{
	char *s = "QQQ";
	strtol(s,NULL,0);
	printf("ERRNO(%d)",errno);
}

and on windows, using MS Visual Studio 6.0 it prints "ERRNO(0)".

Regan
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