The simple answer (there are more complex answers) is to use select()
with a timeout prior to your blocking socket read. Some notes to be
aware of:
* The pointer to struct timeval (last arg) will get modified. You need
to set the struct timeval prior to each call.
* Here is a code clip:
// m_fd is the socket, and m_tv contains a timeout value
ssize_t do_read( int m_fd, const struct timeval *m_tv )
{
int
sval;
ssize_t
nread = 0;
ssize_t
nread = 0; // bytes read from read()
struct timeval // local copy of tv,
tv = *m_tv; // select will modify it
fd_set
fdsr,
fdse;
FD_ZERO( &fdsr ); // and a read set for use with select()
FD_ZERO( &fdse ); // and an error set for use with select()
FD_SET( m_fd, &fdsr ); // m_fd is the socket to read, we're
FD_SET( m_fd, &fdse ); // creating sets for select
// check for read ready for or socket error
sval = select( m_fd+1, &fdsr, NULL, &fdse, &tv );
if( sval > 0 ) // something available to read on m_fd
{
nread = read( ... );
}
else if( sval == 0 )
{
nread = 0; // nothing happened on m_fd, timed out
}
else // select failed
{
nread = errno;
perror( "error" );
}
return nread;
}
FWIW,
Nat
On Mon, 2002-07-29 at 16:42, Frank Samuelson wrote:
>
> I have a client program that performs a recv()
> on a blocking socket. The program catches SIGPIPEs and exits.
>
> When the server computer crashes the client hangs on the recv() call.
> It continues to do so even after the server computer comes back up.
> When the server computer shuts down nicely, or the
> server program is stopped or killed,
> this is not a problem.
>
> Is this standard behavior? If yes, how to I
> hack it so the recv() call times out?
>
> Perhaps I should mention that this connection typically
> carries 6-7 MB/s on a 100Mb connection. No
> data in >10 sec is an almost certain sign of a dead server.
>
> Thanks for any help
>
> -Frank
>
> -
> : send the line "unsubscribe linux-net" in
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--
_________________________________________
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nat.ersoz@myrio.com Cell: 425-417-5182 /\\
Phone: 425.897.7278 Fax: 425.897.5600 _\_V
3500 Carillon Point Kirkland, WA 98033
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