big-file-gen

Small Python CLI tools for creating and reading large files. Useful for storage testing, transfer checks, and dumb-fun disk abuse.

What it does

• create large binary files filled with zeros
• optionally create sparse files instead
• read files back and measure throughput
• optionally compute SHA256 while reading
• no third-party dependencies

Usage

Create a file

python make_big_file.py <output> <size> [--chunk-size SIZE] [--sparse] [--force] [--quiet]

Examples:

python make_big_file.py test.bin 15GB
python make_big_file.py dump.dat 1.5TiB --chunk-size 128MB
python make_big_file.py tiny.bin 500MB --quiet
python make_big_file.py sparse.img 20GB --sparse
python make_big_file.py test.bin 15GB --force

Read a file

python read_big_file.py <input> [--chunk-size SIZE] [--hash] [--quiet]

Examples:

python read_big_file.py test.bin
python read_big_file.py dump.dat --chunk-size 128MB --hash
python read_big_file.py tiny.bin --quiet

Size formats

Binary units are supported:

• B
• KB, MB, GB, TB, PB
• KiB, MiB, GiB, TiB, PiB

Plain numbers are treated as bytes.

Exit codes

• 0 success
• 1 failure
• 130 interrupted

Requirements

• Python 3.8+
• enough disk space for real writes

Notes

• --sparse is handy when you want a huge file without actually burning the disk.
• --force overwrites an existing output file (without it, existing files are protected).
• --hash is SHA256, because anything weaker would be cosplay.