What does “No anode” mean in errno 55 when socket connection fails?

[Polytropon]

On Tue, 29 Dec 2020 13:53:24 -0500, Kevin P. Neal wrote:
> On Sun, Dec 27, 2020 at 11:03:17PM +0530, Rahul Bharadwaj wrote:
> > I was doing a few performance tests on a local server and once in a while I
> > hit an error where opening a socket connection fails.
> > 
> > i.e. considering the simplest code:
> > 
> > #include <errno.h>
> > #include <sys/socket.h>
> > 
> > int main() {
> >     /* code to create socket object */
> > 
> >     int ret = connect(sock, (struct sockaddr *)&serv_addr,
> > sizeof(serv_addr));
> >     if (ret < 0) {
> >         fprintf(stderr, "connect() failed with: %d\n", errno); // <---- *get
> > errno as 55*
> >         exit(1);
> >     }
> >     /* other code */
> > }
> > 
> > There is no explanation for this error number "55". In every place, the
> > only mention is "No anode". There is no mention of what "anode" means and
> > what "No anode" specifically means.
> > 
> > Can someone please help me with what this errno means or point me to some
> > documentation explaining the same.
> 
> Call strerror(errno) to get a char* that describes what the various errno
> values mean. Pass that char* to fprintf with the usual "%s" format string.

Or use perror(), which technically does the same thing (and
allows you to add a custom error message prefix):

     The perror() function finds the error message corresponding to the cur-
     rent value of the global variable errno (intro(2)) and writes it, fol-
     lowed by a newline, to the standard error file descriptor.  If the argu-
     ment string is non-NULL and does not point to the null character, this
     string is prepended to the message string and separated from it by a
     colon and space (``: ''); otherwise, only the error message string is
     printed.

See "man 3 perror" for details.

There is also a perror program, which can be used to check:

	% perror 55
	No buffer space available

See "man 1 perror" for details respectively.






-- 
Polytropon
Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...