I/O multiplexing: select, poll and epoll in Linux
1.0 I/O multiplexing I/O multiplexing is the the ability to perform I/O operations on multiple file descriptors. Input operations like read, accept and calls for receiving messages block when there…
Interprocess Communication using Unix Domain Sockets
1.0 Unix Domain Sockets A socket is a communication endpoint at a host computer. The socket API provides calls for communication between processes. The socket system call is, int socket…
Analyzing the NGINX web server log file
1.0 Introduction Given an nginx web server log file, we might like to know who are the visitors to our website. One can go line by line through the log…
Syslog
1.0 Syslog Syslog is a protocol for conveying event notification messages. Syslog was first developed by Eric Allman for logging as a part of the Sendmail project in the 1980s.…
D-Bus Tutorial
D-Bus is a mechanism for interprocess communication for Linux systems. D-Bus concepts along with example client-server programs are explained.
POSIX message queues in Linux
POSIX message queue calls for interprocess communication (IPC) between processes are explained with an example of server and client programs in C under Linux.
System V message queues in Linux
1.0 Message queues Message queues are one of the interprocess communication mechanisms available under Linux. Message queues, shared memory and semaphores are normally listed as the three interprocess communication mechanisms…
FIFOs in Linux
1.0 FIFO FIFOs are pipes with a name and are also commonly referred to as named pipes. Pipes are common on Linux command lines but do not have a system-wide…
Using Git
1.0 Introduction Git commands for common source code management use cases are listed. 2.0 Install Git On an Ubuntu Linux system, Git can be installed with the command, $ sudo…
Getting WordPress to work with Varnish 4.0
With Varnish 4.0, the VCL has changed. So an update from Varnish 3 .0 to Varnish 4.0 requires a change in the VCL file, /etc/varnish/default.vcl. As a part of Varnish…