Returns the socket descriptor associated with a Socket Device
    Channel (SDC) for direct use with the OpenVMS C Run-Time Library.
    Format
      #include  <socket.h>
      int decc$socket_fd  (int channel);

1  –  Argument

 channel
    A valid SDC.

2  –  Description

    This function associates a valid socket channel with an HP
    C run-time library file descriptor, and returns the file
    descriptor. The file descriptor can then be used with any HP C
    run-time library function that takes a file descriptor or socket
    descriptor as an input parameter.

3  –  Return Values

    x                  The socket descriptor.
    -1                 Indicates an error; the socket descriptor
                       cannot be allocated.