Call a foreign-language function: Difference between revisions
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→{{header|Ruby}}: Add solution using Fiddle. |
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LibC.free(duplicate)
</lang>
=== Fiddle ===
Ruby 1.9.2 added Fiddle to the standard library. DL finds foreign functions, and Fiddle uses libffi to call them. DL and Fiddle are poorly documented. They are not compatible with all platforms.
{{works with|MRI|1.9.2}}
<lang ruby>require 'dl'
require 'fiddle'
# Declare strdup().
# * DL::Handle['strdup'] is the address of the function.
# * The function takes a pointer and returns a pointer.
strdup = Fiddle::Function.new(DL::Handle['strdup'],
[DL::TYPE_VOIDP], DL::TYPE_VOIDP)
# Call strdup().
# * Fiddle converts our Ruby string to a C string.
# * Fiddle returns a DL::CPtr.
duplicate = strdup.call("This is a string!")
# DL::CPtr#to_s converts our C string to a Ruby string.
puts duplicate.to_s
# We must call free(), because strdup() allocated memory.
DL.free duplicate</lang>
=== RubyInline ===
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