7.31 file Day20

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The way meaning "R" opens, read only;

"W" open, the file pointer refers to the head, write only;

"A" opens, pointing to the end of the file, appended to the existing file;

"RB" opens a binary file, read only;

"WB" opens a binary file that is written only;

"AB" opens a binary file, which is appended;

"R+" opens a file that already exists in read/write mode;

"W+" creates a new text file in read/write mode;

"A +" opens a file file for append in read/write mode;

"rb+" opens a binary file in read/write mode;

"Wb+" creates a new binary file in read/write mode;

"ab+" opens a binary file for append in read/write mode;

When a file is opened successfully with fopen (), the function returns a pointer to a file and returns a null pointer if it fails to open.

---note---

7.31 file Day20