function
file_stderr
file_stderr() -> pointer
Returns the handle for the standard-error stream, which you pass to file_write to emit raw bytes. Writing diagnostics and error messages here keeps them separate from normal program output on standard out, so a tool's real results are not mixed with its warnings. It takes no arguments and always refers to the process's standard error. Use it for the error side of command-line tools written in Ludic.
Example
program WarnToStderr {
handler CheckArgs phase Start {
if arg_count() < 2 {
let err = file_stderr()
let message = "missing argument\n"
file_write(err, message, len(message))
exit(1)
}
print("ok")
}
}