# \[BUG\] waitpid for ruby-trunk

**URL:** <https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908>\
**Category:** Development\
**Created:** [March 15, 2007, 3:01pm UTC](https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908 "2007-03-15T15:01:20Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\
**Post date:** [March 15, 2007, 3:01pm UTC](https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908/1 "2007-03-15T15:01:20Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

e$B$3$s$I$Oe(B, ruby-trunk(ruby 1.9.0 (2007-03-14 patchlevel  
0)[i686-linux])  
e$B$NJ}$N%P%0$rJs9p$7$^$9e(B.

e$B2\<5-%9%/%j%W%H$r\<B9T$9$k$He(B, e$BB(:B$Ke(B

#\<Errno::ECHILD: No child processes\>

e$B$,H/@8$7$^$9e(B.

– cut here –

p1 = fork{sleep 10}  
p2 = fork{sleep 10}

Thread.start{  
begin  
puts “wait p#1”  
\_pid = Process.waitpid(p1, nil)  
puts “end p#1”  
rescue  
p $!  
end  
}

Thread.start{  
begin  
puts “wait p#2”  
\_pid = Process.waitpid(p2, nil)  
puts “end p#2”  
rescue  
p $!  
end  
}

sleep 20

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—

---

<div class="post-metadata">

**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\
**Post date:** [March 16, 2007, 4:48am UTC](https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908/2 "2007-03-16T04:48:19Z")

</div>

e$B$J$+$@$G$9!#e(B

At Thu, 15 Mar 2007 22:59:13 +0900,  
Keiju ISHITSUKA wrote in [ruby-dev:30593]:

> e$B$3$s$I$Oe(B, ruby-trunk(ruby 1.9.0 (2007-03-14 patchlevel 0)[i686-linux])  
> e$B$NJ}$N%P%0$rJs9p$7$^$9e(B.
> 
> e$B2\<5-%9%/%j%W%H$r\<B9T$9$k$He(B, e$BB(:B$Ke(B
> 
> #\<Errno::ECHILD: No child processes\>
> 
> e$B$,H/@8$7$^$9e(B.

Linux 2.4e$B$G$7$g$&$+!#e(B2.6e$B$@$H@5\>o$K=\*N;$7$^$9!#e(B  
e$B$?$V$s!"e(Bpthread\_kill()e$B$,@5$7$$Aj\<j$KFO$$$F$J$$$s$8$c$J$$$+$HA[e(B  
e$BA|$7$^$9$,!#e(B

-DTHREAD\_DEBUG=-1e$B$r$D$1$F%3%s%Q%$%k$7$F!"@hF,$Ke(B  
Thread.DEBUG = true  
e$B$r$$$l$F%F%9%H$7$F$\_$F$/$@$5$$!#e(B

# -DTHREAD\_DEBUG=1 e$B$Oe(Bminirubye$B$^$G$K$7$H$$$?$[$&$,L5Fq!#e(B

---

<div class="post-metadata">

**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\
**Post date:** [March 16, 2007, 5:23am UTC](https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908/3 "2007-03-16T05:23:21Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

In [ruby-dev:30598] the message: “[ruby-dev:30598] Re: [BUG] waitpid for  
ruby-trunk”, on Mar/16 12:47(JST)  
Nobuyoshi N. writes:

> e$B$J$+$@$G$9!#e(B

> Linux 2.4e$B$G$7$g$&$+!#e(B2.6e$B$@$H@5\>o$K=\*N;$7$^$9!#e(B

e$B$=$NDL$j$G$9e(B.

> e$B$?$V$s!"e(Bpthread\_kill()e$B$,@5$7$$Aj\<j$KFO$$$F$J$$$s$8$c$J$$$+$HA[e(B  
> e$BA|$7$^$9$,!#e(B
> 
> -DTHREAD\_DEBUG=-1e$B$r$D$1$F%3%s%Q%$%k$7$F!"@hF,$Ke(B  
> Thread.DEBUG = true  
> e$B$r$$$l$F%F%9%H$7$F$\_$F$/$@$5$$!#e(B

Thread.DEBUG= e$B$O$J$$$H%(%i!\<$,=P$^$7$?e(B. Thread::DEBUG = 1  
e$B$G\<B9T$7$^$7e(B  
e$B$?e(B.

> # -DTHREAD\_DEBUG=1 e$B$Oe(Bminirubye$B$^$G$K$7$H$$$?$[$&$,L5Fq!#e(B

e$B2?$H$J$/M}2re(B(^^;

e$B7k2L$O0J2\<$N46$8$G$9e(B. e$B$3$l$G$o$+$j$^$9e(B?  
e$B$A$J$\_$K%F%9%H%9%/%j%W%H$OJQ99e(B  
e$B$7$F$$$Fe(B:

p1 = fork{exec “sleep”, “10”}  
p2 = fork{exec “sleep”, “10”}

e$B$H$J$C$F$$$^$9e(B.

–  
emperor:/home/keiju/var/src/var.lib/ruby/RubyBase/ruby-trunk# ./ruby  
/tmp/test-waitpid.rb  
0x4000 - rb\_thread\_wait\_fd\_rw(5, read)  
0x4000 - enter blocking region (0x81748d8)  
0x4000 - leave blocking region (0x81748d8)  
0x4000 - rb\_thread\_wait\_fd\_rw(5, read): done  
0x4000 - rb\_thread\_wait\_fd\_rw(5, read)  
0x4000 - enter blocking region (0x81748d8)  
0x4000 - leave blocking region (0x81748d8)  
0x4000 - rb\_thread\_wait\_fd\_rw(5, read): done  
0x4000 - create - stack size: 524288  
0x4000 - create: 0x8181510 (0)0x4000 - create - stack size: 524288  
0x8003 - thread start: 0x8181510  
0xc004 - thread start: 0x8186178  
0x4000 - create: 0x8186178 (0)0x4000 - rb\_thread\_schedule  
0x4000 - rb\_thread\_alone: 3  
0x4000 - rb\_thread\_schedule/switch start  
0x8003 - thread start (get lock): 0x8181510  
0x8003 - rb\_thread\_wait\_fd\_rw(1, write)  
0x8003 - enter blocking region (0x8181510)  
0xc004 - thread start (get lock): 0x8186178  
0xc004 - rb\_thread\_wait\_fd\_rw(1, write)  
0xc004 - enter blocking region (0x8186178)  
0x8003 - leave blocking region (0x8181510)  
0x8003 - rb\_thread\_schedule  
0x8003 - rb\_thread\_alone: 3  
0x8003 - rb\_thread\_schedule/switch start  
0x4000 - rb\_thread\_schedule/switch done  
0x4000 - native\_sleep 20  
0x4000 - native\_sleep: pthread\_cond\_timedwait start (1174018444,  
497774000)  
0x8003 - rb\_thread\_schedule/switch done  
0x8003 - rb\_thread\_wait\_fd\_rw(1, write): done  
wait p#1  
wait p#2  
0x8003 - enter blocking region (0x8181510)  
0x8003 - leave blocking region (0x8181510)  
0x8003 - rb\_thread\_wait\_fd\_rw(1, write)  
0x8003 - enter blocking region (0x8181510)  
0x8003 - leave blocking region (0x8181510)  
0x8003 - rb\_thread\_wait\_fd\_rw(1, write): done  
#\<Errno::ECHILD: No child processes\>  
0x8003 - thread end: 0x8181510  
0xc004 - leave blocking region (0x8186178)  
0xc004 - rb\_thread\_wait\_fd\_rw(1, write): done  
0xc004 - enter blocking region (0x8186178)  
0xc004 - leave blocking region (0x8186178)  
0xc004 - rb\_thread\_wait\_fd\_rw(1, write)  
0xc004 - enter blocking region (0x8186178)  
0xc004 - leave blocking region (0x8186178)  
0xc004 - rb\_thread\_schedule  
0xc004 - rb\_thread\_alone: 2  
0xc004 - rb\_thread\_schedule/switch start  
0xc004 - rb\_thread\_schedule/switch done  
0xc004 - rb\_thread\_wait\_fd\_rw(1, write): done  
#\<Errno::ECHILD: No child processes\>  
0xc004 - thread end: 0x8186178

> 

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—

---

<div class="post-metadata">

**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\
**Post date:** [March 17, 2007, 4:54am UTC](https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908/4 "2007-03-17T04:54:24Z")

</div>

e$B$1$$$8$e!w$$$7$D$+$G$9e(B.

In [ruby-dev:30610] the message: “[ruby-dev:30610] Re: [BUG] waitpid  
for ruby-trunk”, on Mar/17 12:16(JST) “KUBO Takehiro” writes:

> e$B5WJ]$G$9!#e(B

> Linux kernel 2.6 e$B$G$b!"4D6-JQ?te(B LD\_ASSUME\_KERNEL=2.4.19  
> e$B$r@\_Dj$7$F!“e(BLinuxThreads e$B$r;HMQ$5$;$k$h$&$K$7$?$i!”:F8=$7$^$7$?!#e(B

> e$B0J2\<$Ne(B LinuxTheads e$B$N@)8B$K$R$C$+$+$C$F$$$k$N$G$7$g$&!#e(B  
> [http://www.linux.or.jp/JM/html/LDP\_man-pages/man7/pthreads.7.html](http://www.linux.or.jp/JM/html/LDP_man-pages/man7/pthreads.7.html)
> 
> > e$B$“$k%9%l%C%I$,e(B fork(2) e$B$r;H$C$F?7$7$$;R%W%m%;%9$r:n@.$7$?\>l9g!“e(B  
> > e$B$I$N%9%l%C%I$G$b$3$N;R%W%m%;%9$re(B wait(2) e$B$G$-$k$Y$-$G$”$k!#$7e(B  
> > e$B$+$7$J$,$i!”$3$N\<BAu$G$O;R%W%m%;%9$r:n@.$7$?%9%l%C%I$@$1$,$3e(B  
> > e$B$N;R%W%m%;%9$re(B wait(2) e$B$G$-$k!#e(B

e$B$J$k$[$Ie(B… e$B$J$+$J$+1|$,?\<$$$G$9$Me(B…

e$B2\<5-%9%/%j%W%H$K$7$?$ie(B Process::wiaitpid  
e$B$,@5\>o$KF0:n$7$^$7$?e(B.  
shell.rb e$B$NJ}$bF1MM$K$7$?$iF0:n$9$k$h$&$K$J$C$?$h$&$G$9e(B.

e$B$"$j$,$H$&$4$6$$$^$7$?e(B.

–  
Thread.start{  
p1 = fork{exec “sleep”, “1”}  
begin  
puts “wait p#1”  
\_pid = Process.waitpid(p1, nil)  
puts “end p#1”  
rescue  
p $!  
end  
}

Thread.start{  
p2 = fork{exec “sleep”, “1”}  
begin  
puts “wait p#2”  
\_pid = Process.waitpid(p2, nil)  
puts “end p#2”  
rescue  
p $!  
end  
}

sleep 20

\_\_  
----------------------------------------------------\>\> e$B@PDMe(B  
e$B7=\<ye(B \<\<—  
----------------------------------\>\> e-mail: removed\_email\_address@domain.invalid \<\<—

---

<div class="post-metadata">

**Author:** ![unknown](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/4bbf92/32.png) [@unknown](https://www.ruby-forum.com/u/unknown)\
**Post date:** [March 17, 2007, 4:17am UTC](https://www.ruby-forum.com/t/bug-waitpid-for-ruby-trunk/88908/5 "2007-03-17T04:17:22Z")

</div>

e$B5WJ]$G$9!#e(B

On 3/16/07, e$B@PDM7=\<ye(B [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

> > Linux 2.4e$B$G$7$g$&$+!#e(B2.6e$B$@$H@5\>o$K=\*N;$7$^$9!#e(B
> 
> e$B$=$NDL$j$G$9e(B.

Linux kernel 2.6 e$B$G$b!"4D6-JQ?te(B LD\_ASSUME\_KERNEL=2.4.19  
e$B$r@\_Dj$7$F!“e(BLinuxThreads  
e$B$r;HMQ$5$;$k$h$&$K$7$?$i!”:F8=$7$^$7$?!#e(B

e$B0J2\<$Ne(B LinuxTheads e$B$N@)8B$K$R$C$+$+$C$F$$$k$N$G$7$g$&!#e(B  
[http://www.linux.or.jp/JM/html/LDP\_man-pages/man7/pthreads.7.html](http://www.linux.or.jp/JM/html/LDP_man-pages/man7/pthreads.7.html)