This document discusses different file input/output operations like creation, opening, reading, writing, seeking, and closing files. It explains how to demonstrate various file concepts like error handling from opening a nonexistent file, and counting characters, newlines, blank spaces, and tabs from within a single program. The document is a lecture on introduction to file I/O in programming.

1. Lecture 21Lecture 21
Version 1.0Version 1.0
Introduction to FileIntroduction to File
I/OI/O

2. 2Rushdi Shams, Dept of CSE, KUET, Bangladesh
Different operations on filesDifferent operations on files
1.1. Creation of a new fileCreation of a new file
2.2. Opening an existing fileOpening an existing file
3.3. Reading from a fileReading from a file
4.4. Writing to a fileWriting to a file
5.5. Moving to a specific location in a file (seeking)Moving to a specific location in a file (seeking)
6.6. Closing a fileClosing a file

3. 3Rushdi Shams, Dept of CSE, KUET, Bangladesh
Various file concepts from oneVarious file concepts from one
programprogram
 Now, we will see various concepts on files fromNow, we will see various concepts on files from
just one program.just one program.

4. 4Rushdi Shams, Dept of CSE, KUET, Bangladesh

5. 5Rushdi Shams, Dept of CSE, KUET, Bangladesh

6. 6Rushdi Shams, Dept of CSE, KUET, Bangladesh

7. 7Rushdi Shams, Dept of CSE, KUET, Bangladesh

8. 8Rushdi Shams, Dept of CSE, KUET, Bangladesh

9. 9Rushdi Shams, Dept of CSE, KUET, Bangladesh
Error opening file??Error opening file??
 While opening the file in “r” mode, this mayWhile opening the file in “r” mode, this may
happen because the file being opened may nothappen because the file being opened may not
be present on the disk at allbe present on the disk at all

10. 10Rushdi Shams, Dept of CSE, KUET, Bangladesh

11. 11Rushdi Shams, Dept of CSE, KUET, Bangladesh
 Now we will write a program that countsNow we will write a program that counts
Character, newlines, blank spaces and tabs fromCharacter, newlines, blank spaces and tabs from
a filea file

12. 12Rushdi Shams, Dept of CSE, KUET, Bangladesh