Purpose of simple wrapper function in C -


in ex26 of 'learn c hard way' in db.c file zed defines 2 functions:

static file *db_open(const char *path, const char *mode) { return fopen(path, mode); } static void db_close(file *db) { fclose(db); }

i have hard time understanding purpose/need wrapping these simple calls fopen , fclose. are, if any, advantages of wrapping simple functions, example given above?

in particular case wrapper used hide detail db_open, db_read or db_close map file operations.

this approach implements abstraction layer through database related functions accessed. provides modularity, may later allow adding more methods open/read/close databases.

as explained michael kohne in comments, wrapper should improved totally hide e.g. type of file *db, substituting struct db_context *context;.


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