decmpfs 0.1.2

Apply OS-level transparent filesystem compression (APFS decmpfs / btrfs / NTFS) to a file in place.
Documentation 
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//! The self-replacing stub binary (feature `exe`). A packer injects a
//! zstd-compressed payload executable into a copy of THIS binary; on first run
//! the copy decompresses the payload, writes it back to disk FS-compressed,
//! atomically replaces itself, and execs it. Every later run is the plain
//! materialized executable — this stub is gone.
//!
//! A bare, unpacked `decmpfs-stub` carries no payload, so `self_replace_and_exec`
//! returns `Ok(false)` and there is nothing to run: it exits non-zero with a
//! diagnostic rather than pretend-succeeding.

fn main() {
  let argv: Vec<String> = std::env::args().collect();
  match decmpfs::exe::self_replace_and_exec(&argv) {
    // Unix: exec replaces the process image, so Ok(true) never actually
    // returns here. Windows spawns the materialized sibling and returns true.
    Ok(true) => {}
    Ok(false) => {
      eprintln!(
        "decmpfs-stub: no packed payload in this binary — pack one in with \
         decmpfs::exe::pack_executable_with_stub before running it."
      );
      std::process::exit(2);
    }
    Err(e) => {
      eprintln!("decmpfs-stub: {e}");
      std::process::exit(1);
    }
  }
}