C Programming Complete Syntax & Pointer Quick Reference Sheet
Compact exam revision cheat sheet summarizing format specifiers, pointer syntax, memory allocation, and file operations in C.
C Programming · CACS101 · Semester 1
Unit 4•Unit 4 of 4
Unit 4: 3. File Opening Modes (`fopen`)
| Mode | Meaning | If File Exists | If File Does Not Exist |
|---|---|---|---|
"r" | Read text | Opens from beginning | Returns NULL (Error) |
"w" | Write text | Overwrites / Truncates | Creates new file |
"a" | Append text | Appends to EOF | Creates new file |
"rb", "wb" | Binary read / write | Same as above | Same as above |
"r+" | Read and write | Opens from beginning | Returns NULL |
CS50x Introduction to C Programming Lecture (David J. Malan)
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Related notes
- C Programming — Complete Course Notes (BCA 1st Sem)Notes
- Unit 1: Introduction to Programming Concepts and C Language NotesNotes
- Unit 2: Operators and Expressions NotesNotes
- Unit 3: Input and Output Operations NotesNotes
- Unit 4: Control Statements and Decision Making NotesNotes
- Unit 5: Arrays and String Manipulations NotesNotes
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