Timers & Sockets

• Download demo C/C++ projects(3) - 68.3 Kb
• Download demo VB projects(2) - 20.5 Kb
• Download distribution - 40 Kb
• Download source - 32.9 Kb
• Download function documentation - 30.5 Kb

Introduction

BOS contains the functionality of the TIM and SOC sub-systems. Seventeen additional routines are provided to satisfy application program requirements in a C/C++ and VB environment. The praxis is that 150TIM+400SOC slots are enough for an application.

Background

Each slot may be set up to signal an event-flag, execute a function, or spin-off a thread; with or without a parameter. A slot is allocated a number (i.e., 1 to 550) on creation. Slots may be removed by slot-number.

Initialization is done when the first call to any relevant routine is made. A slot is set up using make_slot. A slot is destroyed using remove_slot. The BOS sub-system is de-initialized using reset. The user facilitates the actions by calling await_slot.

When a slot is signaled, its actions are performed, unless its action is ‘to return from await_slot’ and we are not in await_slot. When we are, then it will.

A process is expected to set up its slot requirements from any of its threads and then some of these threads spend their time in await_slot. When a thread returns from await_slot, for other than a timeout reason, it will be because a signaled state that has no function or thread entry setup in the relevant slot group has occurred. Having actioned this signaled state, the thread should recall await_slot. Perhaps a common usage will have all slot entries with a function or thread entry point so that the only return from await_slot will be for a timeout reason.

The 'await' and nine 'make' calls take a group number. This allows sub-sets of the collection of slots to be waited on, perhaps by different threads.

Using the code

VC 6.0 projects:

• Place the BOSDLL.dll in a directory on your path variable.
• Add the library BOSDLL.lib to the project resources.
• Add the modules BOScalls.h, SOCcalls.h and TIMcalls.h to the project.
• Use the routines therein.

VB 6.0 projects:

• Register the BOSDLL.dll with regsvr32.
• Add the modules BOSDLL.bas, SOCDLL.bas and TIMDLL.bas to the project.
• Use the public routines therein.

//
// Source code to produce the above console screen
// is to be found in the 1st of the 3 demo C/C++ projects.
//

History

• 3.4 - BOS_Src.cpp - Comment/Logging maintenance.
• 3.3 - For C/C++ only users, a static library can be built using the workspace and the project files provided.
• 3.2 - Server-side 'select' timeout is reduced from 50 to 1 millisecond. This allows faster transfer, though one's machine will get busier.