process.bend source

process.bend on the hub · documented module

# Subprocesses and process-level OS access, with byte-exact input and output.import Baseimport 0xbf22530d1ea11c951d1ecaa353ed1580/bytes.bend as Bytes# Environment entries are KEY=VALUE; they override inherited variables.# The command is an executable name or path, never a shell expression.# Exit status is 0..255, or 128 + the terminating signal number.def run.raw(cmd: String, args: List<&2, String>, env: List<&2, String>, stdin: String) ->  IO(Result<&1, &1, U32 & String, U32 & String & String>):  import "./effs/process.c"  import "./effs/process.js"# A streaming child: pid, writable stdin, readable stdout and stderr.# Close stdin to send EOF; drain both outputs before wait to avoid pipe deadlock.def spawn(cmd: String, args: List<&2, String>, env: List<&2, String>) ->  IO(Result<&1, &1, U32 & String, U32 & File & File & File>):  import "./effs/process.c"  import "./effs/process.js"# Reaps a spawned child. A signaled child has status 128 + signal number.def wait(pid: U32) -> IO(Result<&1, &1, U32 & String, U32>):  import "./effs/process.c"  import "./effs/process.js"# Read up to max bytes from this program's standard input; empty at EOF.def read_stdin(max: U32) -> IO(Result<&1, &1, U32 & String, String>):  import "./effs/process.c"  import "./effs/process.js"def stdin.read(max: U32) -> IO(Result<&1, &1, U32 & String, String>):  read_stdin(max)# Terminates this program with the supplied status.def exit.raw(code: U32) -> IO(Unit):  import "./effs/process.c"  import "./effs/process.js"def exit(code: U32) -> IO(Unit):  exit.raw(code)def cwd() -> IO(Result<&1, &1, U32 & String, String>):  import "./effs/process.c"  import "./effs/process.js"def chdir(path: String) -> IO(Result<&1, &1, U32 & String, Unit>):  import "./effs/process.c"  import "./effs/process.js"def hostname() -> IO(Result<&1, &1, U32 & String, String>):  import "./effs/process.c"  import "./effs/process.js"def pid() -> IO(U32):  import "./effs/process.c"  import "./effs/process.js"# Install SIGINT/SIGTERM handlers and take one pending event; 0 means none.def signal.poll() -> IO(U32):  import "./effs/process.c"  import "./effs/process.js"def run.result(r: Result<&1, &1, U32 & String, U32 & String & String>) ->  Result<&1, &1, U32 & String, U32 & Bytes.Bytes & Bytes.Bytes>:  match r:    case Fail{err}:      Fail{err}    case Done{(code, out, err)}:      Done{(code, Bytes.from_string(out), Bytes.from_string(err))}def run(cmd: String, args: List<&2, String>, env: List<&2, String>, stdin: Bytes.Bytes) ->  IO(Result<&1, &1, U32 & String, U32 & Bytes.Bytes & Bytes.Bytes>):  do IO<Result<&1, &1, U32 & String, U32 & Bytes.Bytes & Bytes.Bytes>>:    result : Result<&1, &1, U32 & String, U32 & String & String> <-      run.raw(cmd, args, env, Bytes.to_string(stdin))    return run.result(result)