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ForeignFunctions :: foreignSymbol

foreignSymbol -- get a foreign symbol

Synopsis

Usage:

foreignSymbol(lib, symb, T)

foreignSymbol(symb, T)
Inputs:
- lib, a shared library,
- symb, a string,
- T, a foreign type,
Outputs:
- a foreign object,

Description

This function is a wrapper around the C function dlsym. It loads a symbol from a shared library using the specified foreign type.

i1 : mps = openSharedLibrary "mps"

o1 = mps

o1 : SharedLibrary

i2 : cplxT = foreignStructType("cplx_t", {"r" => double, "i" => double})

o2 = cplx_t

o2 : ForeignStructType

i3 : foreignSymbol(mps, "cplx_i", cplxT)

o3 = HashTable{i => 1}
               r => 0

o3 : ForeignObject of type cplx_t

If the shared library is already linked against Macaulay2, then it may be omitted.

i4 : foreignSymbol("cplx_i", cplxT)

o4 = HashTable{i => 1}
               r => 0

o4 : ForeignObject of type cplx_t

Ways to use `foreignSymbol` :

"foreignSymbol(SharedLibrary,String,ForeignType)"
"foreignSymbol(String,ForeignType)"

For the programmer

The object foreignSymbol is a method function.