Re: How does one get the description of an errno value

[Steve Graegert <graegerts@gmail.com>]

Tiago,

You're correct.  MAX_ERRNO is a custom macro being defined elsewhere
and actually expands to to sys_nerr.  I picked that code from some
examples I've prepared some years ago.  Sorry for the inconvenience
but I think you get the idea.  see perror(3) for more info.

	\Steve

--

Steve Graegert
www.graegert.com



On Sun, Mar 15, 2009 at 11:43 AM, Tiago Maluta
<maluta_tiago@yahoo.com.br> wrote:
> Steve,
>
>> The following code snippet should do it.  It basically sets errno
>> manually and outputs the associated error message.
>>
>> --- BEGIN ---
>>
>> #define _ALL_SOURCE
>>
>> #include <stdio.h>
>> #include <errno.h> /* for _MAX_ERRNO */
>>
>
> I've searched in headers on /usr/include for MAX_ERRNO but not found.
> Where MAX_ERRNO is defined?
>
> A *very* simple workaround was check for "Unknown" word, so I tried:
>
> int main(void) {
>        int i=0;
>        extern int errno;
>        char str[128];
>
>        while (strncmp(str,"Unknown",7)) {
>                sprintf(str,"%s",strerror(i));
>                fprintf(stderr, "%3d", i);
>                errno = i;
>                perror(" ");
>                i++;
>        }
>
>        return (0);
> }
>
>
> But there is "Unknown" between valid error messages.
> I think there is a better way to do it....
>
>
> Best regards,
>
> --tm
>
>
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