• 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 under Linux. Semaphores, though, are really for process synchronization. In practice, shared memory, aided by semaphores, makes an interprocess communication mechanism. Message queues is the other ...

  • 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 name. So, any two processes that wish to communicate using a pipe need to be related, either parent and child or, sharing a common parent, who ...

  • Pipes in Linux

    1.0 Interprocess communication

    A process is an active operating system entity which executes programs. Normally, a process, like a specialist, does one particular job (well). In real life, there are complex workflows and we, often, have multiple processes collaborating to accomplish certain objectives. In order to work together, processes need to exchange data. ...

  • fork and exec system calls in Linux

    1.0 fork and exec system calls

    Suppose we wish to write a “shell program” which would execute another program. Now, in a computing system, a process executes a program. So this shell program (or, process, at run time) needs to create a process which would execute a program. Here, two system calls are ...

  • Program, Process and Threads


    The definition of program is linked to the definition of algorithm. An algorithm is a sequence of finite steps which can be executed mechanically to solve a problem. The key points are that algorithms are self-contained; the steps given are sufficient to solve the problem at hand. No additional information is required. Also, ...