fc

Fast CLI tool that counts files and/or directories using Linux getdents64 (optional recursion, adjustable buffer).

Usage

Build:

cargo build --release

Run:

target/release/fc [OPTIONS] [PATH]

Options:

• -r, --recursive — Recursively walk subdirectories
• -D, --dirs — Count directories (instead of files)
• -A, --all — Count both files and directories (overrides the default of counting files only)
• -b, --buf-mb — Buffer size in MiB for SYS_getdents64 (default: 5)
• PATH — Directory to traverse (default: .)

Examples:

• Count files in current directory: fc
• Count directories only: fc -D
• Count both files and directories: fc -A
• Count files recursively: fc -r
• Count directories recursively under /var/log: fc -rD /var/log
• Increase buffer to 8 MiB and recurse: fc -b 8 -r

Benchmark and test data:

• Use scripts/gen_bench.sh to generate large test sets and benchmark fc vs ls -1U | wc -l.

Benching

$ ./scripts/gen_bench.sh 
[1/4] Preparing directory: ./testdir (files: 1000000)
[2/4] Generating files...
xargs: warning: options --max-args and --replace/-I/-i are mutually exclusive, ignoring previous --max-args value
[3/4] Building fc (release)...
    Finished `release` profile [optimized] target(s) in 0.01s
Sanity: fc=1000000, ls|wc=1000000
real=0:00.16 user=0.00 sys=0.15 maxrss=7400KB
real=0:00.26 user=0.09 sys=0.17 maxrss=3456KB

License

MIT