1. A method for facilitating identifying a system call in an application and replacing the identified system call with a customized function call, comprising: executing an executable file of the application, wherein the executable file has been modified to execute a hooking and injection manager at run time; and prior to executing the system call, executing the hooking and injection manager, which comprises: determining, from a symbol table, a symbol table index value corresponding to a symbol associated with the system call; determining an import table entry storing a pointer to the system call based on the symbol table index value; and changing the pointer in the import table entry so that the pointer indicates an address of the customized function call.