| OCR Text |
Show fp inited number forms comment (string) end ian float form info (pointer) shared_objs (pointer) next (pointer) Figure ~).5. a.Lstream_type :30 01w sL r<' etlll ohjed. i.-.; associ att'd with each pers ist e nt 1/ 0 st ream (e .g., input , output , ip c). Sin ce the bin a ry fi le may contain objects of classes that are not known to an application, fil e object descrip tors whi ch differ from compiled- in descriptors are saved with the st ream (see Figure 3.5). The stream object a lso records machine inforrnation in the binary fi le required for conversion from one a rch i teet u re to a not he r. • shared_t ab/e_type To store and retrieve object-graphs with shared structures, a ll obj ects are entered in a sharecLtable. Thi s table ide ntifies shared structures on writing and facilitates reconstruction on loading. The sha red table is valid for one Alpll a_ l file onl y. It is flu shed before reading a new Alph a_l-flle from the stand ard input. 3.4.2 Saving & Loading Objects A geometric model consists of a li st of object graphs. For saving the geometric II!Oclel on secondary sto rage, first t he machine information is written to t he binary output f11e and th en all object headers are written out. After this, a. pre-order Lra.versa.l of a ll objects in the graph is done, see Algorithm 1. For each object, the |
