Regex doesn't match - what am I doing wrong?

From: Sriram (mailsb04-posts_at_yahoo.com)
Date: 03/10/04 

Date: 10 Mar 2004 14:53:09 -0800

Hi,

I am having trouble matching a regex that combines a negated character
class and an anchor ($). Basically, I want to match all strings that
don't end in a digit. So I tried:

bash-2.05a@bermuda:15$perl -e 'while (<STDIN>) { if (/[^0-9]$/) {
print;}}'
skdsklds
skdsklds
sklskl2 <== why does this match? it ends in a digit.
sklskl2

This matched all strings regardless of whether or not they ended in a
digit. But the complemented regex seems to work fine:

bash-2.05a@bermuda:13$perl -e 'while (<STDIN>) { if (/[0-9]$/) {
print;}}'
sdkldsklds2
sdkldsklds2
sdsk2
sdsk2
sks <==== doesn't match as expected

I replaced [0-9] with [\d] but got the same results.

On the other hand, grep works as expected:

bash-2.05a@bermuda:9$grep '[0-9]$'
sdksdjk2
sdksdjk2
22221
22221
sdjkdsjk <== doesn't match as expected

bash-2.05a@bermuda:11$grep '[^0-9]$'
sdklsdklds
sdklsdklds
sdkldslk2 <== doesn't match as expected

What am I doing wrong? Here's the perl version info:

bash-2.05a@bermuda:17$perl -V
Summary of my perl5 (revision 5.0 version 6 subversion 1)
configuration:
  Platform:
    osname=linux, osvers=2.4.17-0.13smp, archname=i386-linux
    uname='linux daffy.perf.redhat.com 2.4.17-0.13smp #1 smp fri feb 1
10:30:48 est 2002 i686 unknown '
    config_args='-des -Doptimize=-O2 -march=i386 -mcpu=i686 -Dcc=gcc
-Dcf_by=Red Hat, Inc. -Dcccdlflags=-fPIC -Dinstallprefix=/usr
-Dprefix=/usr -Darchname=i386-linux -
Dvendorprefix=/usr -Dsiteprefix=/usr -Uusethreads -Uuseithreads
-Uuselargefiles -Dd_dosuid -Dd_semctl_semun -Di_db -Di_ndbm -Di_gdbm
-Di_shadow -Di_syslog -Dman3ext=3pm
'
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=undef use5005threads=undef useithreads=undef
usemultiplicity=undef
    useperlio=undef d_sfio=undef uselargefiles=undef usesocks=undef
    use64bitint=undef use64bitall=undef uselongdouble=undef
  Compiler:
    cc='gcc', ccflags ='-fno-strict-aliasing -I/usr/local/include',
    optimize='-O2 -march=i386 -mcpu=i686',
    cppflags='-fno-strict-aliasing -I/usr/local/include'
    ccversion='', gccversion='2.96 20000731 (Red Hat Linux 7.2
2.96-109)', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define,
longdblsize=12
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=4
    alignbytes=4, usemymalloc=n, prototype=define
  Linker and Libraries:
    ld='gcc', ldflags =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib
    libs=-lnsl -ldl -lm -lc -lcrypt -lutil
    perllibs=-lnsl -ldl -lm -lc -lcrypt -lutil
    libc=/lib/libc-2.2.5.so, so=so, useshrplib=false,
libperl=libperl.a
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef,
ccdlflags='-rdynamic'
    cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib'

Characteristics of this binary (from libperl):
  Compile-time options:
  Built under linux
  Compiled at Apr 1 2002 12:23:22
  @INC:
    /usr/lib/perl5/5.6.1/i386-linux
    /usr/lib/perl5/5.6.1
    /usr/lib/perl5/site_perl/5.6.1/i386-linux
    /usr/lib/perl5/site_perl/5.6.1
    /usr/lib/perl5/site_perl/5.6.0
    /usr/lib/perl5/site_perl
    /usr/lib/perl5/vendor_perl/5.6.1/i386-linux
    /usr/lib/perl5/vendor_perl/5.6.1
    /usr/lib/perl5/vendor_perl
    .

Thanks for your help,
Sriram

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