C Programming - MCQ Practice Questions

Which statement correctly counts non-comment lines in a text file?

In a program processing a CSV file, what is the most robust approach for reading variable-length lines?

A file opened with 'r+b' mode has pointer at position 100. After fwrite(buffer, 1, 50, fp), the pointer is at:

Which approach correctly implements a file copy function for both text and binary files?

A program crashes after reading a file. What's most likely the cause if error checking is minimal?

For a file with 1000 records, which approach minimizes I/O operations?

What does rewind(fp) accomplish compared to fseek(fp, 0, SEEK_SET)?

A program processes encrypted binary data with fread(). Why might using 'r' mode instead of 'rb' cause corruption?

For competitive exam file validation: A 2GB file must be processed without loading entirely in memory. Which strategy is optimal?

When implementing a log file writer with concurrent access, what's the critical issue with standard fopen()?

A program reads serialized objects using fread(). What's the primary risk when file format changes between versions?

Which function is used to check if the end-of-file (EOF) has been reached in C file handling?

In a file processing application, what is the primary difference between 'wb' and 'w' file modes?

A program needs to read and write to the same file alternately. Which file mode is most appropriate?

What will be the output of fseek(fp, -10, SEEK_END) in a file of 100 bytes?

In a data structure serialization scenario, what is returned by fwrite() on successful completion?

A competitive exam question requires processing a 500MB CSV file line by line. Which approach is most efficient in terms of memory?

What is the critical issue if ferror(fp) returns non-zero during file operations in a banking application?

For implementing a file locking mechanism in a competitive exam environment, which approach correctly handles concurrent file access in POSIX systems?

In a program that processes binary files with variable-length records, what could cause fread() to return fewer items than requested without reaching EOF?