19 GH: A Portable C to Scheme Interface

This chapter shows how to use the GH interface to call Guile from your application's C code, and to add new Scheme level procedures to Guile whose behaviour is specified by application specific code written in C.

• gh preliminaries
• Data types and constants defined by gh
• Starting and controlling the interpreter
• Error messages
• Executing Scheme code
• Defining new Scheme procedures in C
• Converting data between C and Scheme
• Type predicates
• Equality predicates
• Memory allocation and garbage collection
• Calling Scheme procedures from C
• GH Input/Output
• Mixing gh and scm APIs