present integer indicates if the speech functions of Speech Pack
can succesfully be called.
At the moment these values can be returned:
-1 Speeck Pack is disabled by the SPEECH OFF command.
0 Speech Pack not usable, external package functions
can't be called.
1 Speech Pack usable, external package functions can be
called.
(2 and higher may be used later when other abilities are
added to the Speech Manager and these are implemented in
this external, so every value greater than zero implies
Speech Pack is available.)
Returns an integer indicating if you can use the Speech Pack functions to produce speech.
If SP Can Speak returns a value greater than zero, all other functions can be used (except SP Count voices, SP VERSION and SP COPYRIGHT whom can always be called).
However, when the value returned is zero or negative and you call any of the other functions an error will be returned (-4).
When this function returns zero this means there are one or more conditions not met:
1) the Speech Manager is not installed (use SP VERSION to see if this
is the case)
2) Speech Pack was unable to set up its private data when the data-base
was launched, perhaps because not enough memory was available
(only 984 bytes needed!).
3) when using a time-limited beta-version of Speech Pack the expiration
date may have been passed and the external package refuses to
function.
4) when using Speech Pack together with 4D Server the maximum
