.help zlocpr May84 "System Interface"
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NAME
zlocpr -- get the entry point address of a procedure
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SYNOPSIS
.nf
zlocpr (procedure, address)

extern	procedure()		# external procedure
int	address			# address of the procedure
.fi
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DESCRIPTION
The entry point address (EPA) of \fIprocedure\fR is returned in the integer
variable or integer array element \fIaddress\fR.
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RETURN VALUE
The EPA of a procedure is a magic integer value.  Two EPA values may be
compared for equality to determine if they refer to the same procedure,
and a procedure referenced by an EPA may be executed by passing the EPA
and any arguments to a \fBzcall\fR primitive.
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NOTES
A legal EPA may not have the value NULL, which is reserved for flagging
uninitialized EPA variables.  The Fortran 77 alternate return from subroutine
feature may not be used with \fBzlocpr\fR and \fBzcall\fR because it involves
an extra hidden argument on some systems.  The alternate return feature is
inadvisable for other reasons as well and is forbidden in SPP programs.
Only untyped procedures are permitted, i.e., \fBzlocpr\fR may not be used
with functions.
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SEE ALSO
zcall, zlocva
.endhelp
