Powerful terminal execution, everywhere.

from kryon import Runtime

runtime = Runtime(encoding="utf-8")
result = runtime.execute("git", ["log", "--oneline", "-5"])

print(result.stdout)
print(result.exit_code, result.ok, result.duration)

# A non-zero exit is information, not an exception.
changed = runtime.execute("git", ["diff", "--quiet"]).exit_code == 1

from kryon import Runtime, Stream

runtime = Runtime()

# Output arrives as it is produced, through a bounded queue.
with runtime.spawn("pip", ["install", "numpy"]) as proc:
    for stream, chunk in proc:
        where = "err" if stream is Stream.STDERR else "out"
        print(f"[{where}] {chunk.decode()}", end="")

    result = proc.wait()

# Leaving the block terminates the process. Always.

filename = input("file: ")      # "; rm -rf ~"

# Safe. One literal argument. No shell is involved.
runtime.execute("wc", ["-l", filename])

# Command injection — and it is named so that it looks like one.
runtime.execute_shell(f"wc -l {filename}")

# Keep your credentials out of the child process.
runtime.execute(
    "./untrusted-build.sh",
    clear_env=True,
    env={"PATH": "/usr/bin:/bin", "HOME": "/tmp/build"},
)

import asyncio
from kryon.aio import AsyncRuntime

async def main():
    runtime = AsyncRuntime(encoding="utf-8")

    results = await asyncio.gather(
        runtime.execute("git", ["rev-parse", "HEAD"]),
        runtime.execute("git", ["status", "--porcelain"]),
    )

    # Cancelling the task terminates the child before CancelledError propagates.
    task = asyncio.create_task(runtime.execute("./forever"))
    await asyncio.sleep(1)
    task.cancel()

asyncio.run(main())

result = runtime.execute(
    "./slow-thing",
    timeout=30,                  # terminate, wait kill_grace, then kill
    max_output_bytes=1 << 20,     # per stream, enforced during the flood
)

if result.termination.value == "TIMEOUT":
    # Output collected before the kill is kept — it is the only
    # evidence of what the process was doing.
    print(result.stdout)

# These keep YOUR process healthy. They do not contain a hostile one.