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Read File

Zero-dependency Python snippets for reading files using the standard library.

4 snippets available in this sub-category.

Simple

Read entire file as string

file read string open

Read entire file content as a single string

with open("file.txt", "r") as f:
    content = f.read()
print(content)

Notes

  • Use 'r' mode for text files
  • File is automatically closed after reading
  • Returns empty string if file is empty

Read file with encoding

file read encoding utf-8

Read file with specific encoding

with open("file.txt", "r", encoding="utf-8") as f:
    content = f.read()
print(content)

Notes

  • Always specify encoding for international text
  • UTF-8 is the most common encoding
  • Handles special characters properly

Complex

Read file with error handling

file read error-handling function encoding

Read file with comprehensive error handling and encoding support

def read_file_safe(filename, encoding="utf-8"):
    """Read file with comprehensive error handling."""
    try:
        with open(filename, "r", encoding=encoding) as f:
            return f.read()
    except FileNotFoundError:
        print(f"Error: File '{filename}' not found")
        return None
    except PermissionError:
        print(f"Error: No permission to read '{filename}'")
        return None
    except UnicodeDecodeError:
        print(f"Error: Unable to decode '{filename}' with {encoding} encoding")
        return None


content = read_file_safe("file.txt")
if content:
    print(content)

Notes

  • Handles common file reading errors
  • Returns None on error for easy checking
  • Supports custom encoding
  • Provides helpful error messages

Read file in chunks

file read chunks generator memory-efficient

Read large files in chunks to manage memory efficiently

def read_file_chunks(filename, chunk_size=1024):
    """Read file in chunks to handle large files efficiently."""
    with open(filename, "r") as f:
        while True:
            chunk = f.read(chunk_size)
            if not chunk:
                break
            yield chunk


# Process large file in chunks
for chunk in read_file_chunks("large_file.txt", chunk_size=4096):
    print(f"Processing chunk: {len(chunk)} characters")
    # Process chunk here

Notes

  • Uses generator to yield chunks
  • Prevents loading entire large file into memory
  • Customizable chunk size
  • Useful for processing large log files or datasets

🔗 Cross-References

🏷️ Tags

file, read, text, io

📝 Notes

  • Use open() with mode 'r' to read text files
  • Returns file content as a string
  • Useful for configuration, data, and logs