Open Tcp
 
Opens a TCP client connection and binds it to a file number.

Syntax

Declare Function Open Tcp ( options As String, As [#]filenumber As Long ) As Long

Usage

result = Open Tcp( options[,] As [#]filenumber )
Open Tcp options As [#]filenumber

Parameters

options
A comma-separated string describing the connection.
filenumber
The file number to bind to the connected socket.

Return Value

Returns zero (0) on success, or a non-zero error code on failure.

Description

Open Tcp connects to a TCP server and exposes the socket through FreeBASIC's normal file I/O statements. Once opened, the file number can be used with Print #, Line Input #, Input(), Get #, and Put #.

The options string accepts:
    • host=name-or-address, required for client connections
    • port=number, required
    • timeout=milliseconds, optional socket timeout

Unknown options are ignored so that future TCP options can be added without breaking existing programs.

For sockets, EOF means that no byte is currently available to read. Use Eoc to test whether the peer has closed the connection.

Example

See examples/network/opentcp/http-get.bas.

Platform Differences

  • TCP support is not available on all targets. Programs that need to be portable should use target defines such as FB_DOS, FB_JS, and FB_XBOX where appropriate.

Differences from QB

  • New to FreeBASIC.

See also