ocr: he - symbolic constants in fcnt.h that are used to ppen a file can be combined with the bitwise OR pperator. Here, weare specifying that the file is tobe opened for writing only, that the file is to be opened exclusively, and that the file is to be created ifit doess not exist. 0 EXCL gets used only with ) CRLAL. If the file is created, then the third argument sets the file permissions; otherwise, the argument has no effect. We will explain about file permissions later on.
