id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	difficulty
1486	Reading and writing to a pipe set up by process can cause scheduler assertion errors	sjamaan		"As pointed out in [[https://stackoverflow.com/questions/51344859/connecting-to-interactive-tools-using-chicken-schemes-process|this StackOverflow post]]:

{{{
(use posix)
(let-values (((in out pid) (process ""bc"")))
  (begin
    (display ""2 + 2\n"" out)
    (print (read-line in))))
}}}

Causes the following crash when evaluated:

{{{
thread is registered for I/O on unknown file-descriptor: 4 (expected 3)
[] 
...more...
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<syntax>
<eval>
<eval>
<eval>
<eval>
<eval>  <--
}}}

This bug is not easy to trigger.  I happened to get ""lucky"" and it crashed the first time, but after that I tried again several times and it just worked."	defect	new	major	6.0.0	core libraries	4.13.0				hard