Given the URL: http://www.mydomain.com/myWebApp/theServlet/p1/p2/p3;sid=123?param=abc This would be the output of the various method calls on HttpServletRequest : String scheme = request.getScheme(); // ...

A simple single threaded echo server: #include <stdio.h> #include <stdlib.h> #incl...

There are two ways you cat get the name of a host from its ip address: getnameinfo and gethostbyaddr . The former is IPV6 compatible. Using getnameinfo : #include <sys/types.h> #include <sys/socket.h> ... Using gethostbyaddr : #include <sys/types.h> #include <sys/socket.h> ...

import java.text.DateFormat; import java.text.S... Output: Date LONG format: November 28, 2011 Date MEDIUM...

I always used two steps to extract a gzip tar file: gzip -d somefile.tar.gz tar -xvf somefile.tar Today I learned to do that in one step: tar -zxvf somefile.tar.gz

Copied verbatim from The GNU C Library Manual . When you have finished using a socket, you can simply close its file descriptor with close ; see Opening and Closing Files . If there is still data waiting to be transmitted over the connection, normally close tries to complete this transmission. You can control this behavior using the SO_LINGER socket option to specify a timeout period; see Socket Options . You can also shut down only reception or transmission on a connection by calling shutdown , which is declared in sys/socket.h . Function: int shutdown (int socket, int how) The shutdown function shuts down the connection of socket socket. The argument how specifies what action to perform: 0 - Stop receiving data for this socket....

tcpdump is capable of capturing traffic between two hosts other than the host on which you are running tcpdump. Sometimes, you only see traffic to and from the capturing host and broadcasts from a third host. This could be that your hosts are connected by a switch , as explained by the TCPDUMP FAQ .

#include <stdio.h> #include <stdlib.h> #incl... UNIXguide.net explains this option well: This socket option tells the kernel that even if this port is busy (in the TIME_WAIT state), go ahead and reuse it anyway. If it is busy, but with another state, you will still get an address already in use error. It is useful if your server has been shut down, and then restarted right away while sockets are still active on its port. You should be aware that if any unexpected data comes in, it may confuse your server, but while this is possible, it is not likely. It has been pointed out that "A socket is a 5 tuple (proto, local addr, local port, remote addr, remote port). SO_REUSEADDR just says that you...

Three APIs for event based non-blocking I/O: select() select() is limited to FD_SETSIZE handles. This limit is compiled in to the standard library and user programs. poll() There is no hardcoded limit to the number of file descriptors poll() can handle, but it does get slow about a few thousand. epoll() The epoll event mechanism is much more scalable than the traditional poll when there are thousands of file descriptors in the interest set. The work done by poll depends on the size of the interest set whereas with epoll (like Solaris /dev/poll ) the registration of interest is separated from the retrieval of the events. Reference: The C10K problem

The longjmp function jumps to the line where setjmp was last called. In return, setjmp returns the value passed in as the second parameter to longjmp . #include <stdio.h> #include <stdlib.h> #incl... Result: $ ./longjmp val is 0 val is 1 --> val is ...