# Appendline Invalid read of size 1

**URL:** <https://www.ruby-forum.com/t/appendline-invalid-read-of-size-1/124129>\
**Category:** Development\
**Created:** [December 25, 2007, 6:59am UTC](https://www.ruby-forum.com/t/appendline-invalid-read-of-size-1/124129 "2007-12-25T06:59:59Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Tanaka\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/t/c67d28/32.png) [@Tanaka\_A](https://www.ruby-forum.com/u/Tanaka_A)\
**Post date:** [December 25, 2007, 6:59am UTC](https://www.ruby-forum.com/t/appendline-invalid-read-of-size-1/124129/1 "2007-12-25T06:59:59Z")

</div>

e$B0J2\<$N$h$&$K!"e(Bappendline e$B$,%P%C%U%!$r1[$($?$H$3$m$Ge(B  
onigenc\_get\_left\_adjust\_char\_head e$B$r8F$S=P$7$F$$$k$N$,4Q;!$5e(B  
e$B$l$^$9!#e(B

% valgrind ./ruby -ve ’  
open(“zz”, “wb”) {|f|  
f \<\< (“a”\*8191+"\n")  
}  
open(“zz”, “r:utf-8”) {|f|  
p f.gets.squeeze  
}  
’  
==31497== Memcheck, a memory error detector.  
==31497== Copyright © 2002-2006, and GNU GPL’d, by Julian Seward et  
al.  
==31497== Using LibVEX rev 1658, a library for dynamic binary  
translation.  
==31497== Copyright © 2004-2006, and GNU GPL’d, by OpenWorks LLP.  
==31497== Using valgrind-3.2.1-Debian, a dynamic binary instrumentation  
framework.  
==31497== Copyright © 2000-2006, and GNU GPL’d, by Julian Seward et  
al.  
==31497== For more details, rerun with: -v  
==31497==  
ruby 1.9.0 (2007-12-25 revision 0) [i686-linux]  
==31497== Invalid read of size 1  
==31497== at 0x810E3C0: utf8\_left\_adjust\_char\_head (utf8.c:476)  
==31497== by 0x80B57A0: onigenc\_get\_left\_adjust\_char\_head  
(regenc.c:363)  
==31497== by 0x806C33B: appendline (io.c:1691)  
==31497== by 0x806C6A9: rb\_io\_getline\_fast (io.c:1784)  
==31497== by 0x806C9B7: rb\_io\_getline\_1 (io.c:1863)  
==31497== by 0x806CCB4: rb\_io\_getline (io.c:1922)  
==31497== by 0x806CD1F: rb\_io\_gets\_m (io.c:1961)  
==31497== by 0x80FCFBA: call\_cfunc (vm\_insnhelper.c:281)  
==31497== by 0x810499F: vm\_call\_cfunc (vm\_insnhelper.c:371)  
==31497== by 0x810450C: vm\_call\_method (vm\_insnhelper.c:503)  
==31497== by 0x8100CC6: vm\_eval (insns.def:1050)  
==31497== by 0x8104B78: vm\_eval\_body (vm.c:1148)  
==31497== Address 0x45AC740 is 0 bytes after a block of size 8,192  
alloc’d  
==31497== at 0x401D38B: malloc (vg\_replace\_malloc.c:149)  
==31497== by 0x8061FBD: ruby\_xmalloc (gc.c:249)  
==31497== by 0x8062055: ruby\_xmalloc2 (gc.c:269)  
==31497== by 0x806B358: io\_fillbuf (io.c:989)  
==31497== by 0x806C5E0: appendline (io.c:1736)  
==31497== by 0x806C6A9: rb\_io\_getline\_fast (io.c:1784)  
==31497== by 0x806C9B7: rb\_io\_getline\_1 (io.c:1863)  
==31497== by 0x806CCB4: rb\_io\_getline (io.c:1922)  
==31497== by 0x806CD1F: rb\_io\_gets\_m (io.c:1961)  
==31497== by 0x80FCFBA: call\_cfunc (vm\_insnhelper.c:281)  
==31497== by 0x810499F: vm\_call\_cfunc (vm\_insnhelper.c:371)  
==31497== by 0x810450C: vm\_call\_method (vm\_insnhelper.c:503)  
“a\n”  
==31497==  
==31497== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 21 from  
1)  
==31497== malloc/free: in use at exit: 991,997 bytes in 7,718 blocks.  
==31497== malloc/free: 8,604 allocs, 886 frees, 1,151,047 bytes  
allocated.  
==31497== For counts of detected errors, rerun with: -v  
==31497== searching for pointers to 7,718 not-freed blocks.  
==31497== checked 797,992 bytes.  
==31497==  
==31497== LEAK SUMMARY:  
==31497== definitely lost: 0 bytes in 0 blocks.  
==31497== possibly lost: 68 bytes in 1 blocks.  
==31497== still reachable: 991,929 bytes in 7,717 blocks.  
==31497== suppressed: 0 bytes in 0 blocks.  
==31497== Reachable blocks (those to which a pointer was found) are not  
shown.  
==31497== To see them, rerun with: --show-reachable=yes