Front page | perl.perl5.porters |
Postings from November 1999
Hi!
> Ilya> Without further explanation I hardly think this is a solution. The
> Ilya> real problem is that putenv() of Term::ReadLine::Gnu is mentioning a
> Ilya> wrong malloc() [though I have no idea how this might have happened -
> Ilya> but it does, at least on Solaris 2.7].
>
> I agree with you. Something wrong around malloc().
Nope. It's completly related to free()ing memory which hasn't been
malloc()'ed before. There can't be such a thing like the "wrong
malloc()" since my perl has been build with "usemymalloc=n". I'll
append the testcase and perl version info. The test
if (environ == PL_origenviron)
in util.c:my_setenv() assumes that the char **environ will only be
modified by perl itself. This assumption doesn't always hold true if
some Perl XS module calls putenv(3) before the first call to my_setenv().
> But I feel strange by seeing the patch.
>[...]
> >> - if (environ == PL_origenviron) { /* need we copy environment? */
>
> is true, only when my_setenv() is called at the first time only. And
> Joerg's patch should work as same as original code. I do not
> understand why the patch works.
The patch works because it makes sure that perl only free()'s memory
that has been allocated before. The test via a static variable is
stronger than the comparison to the saved environ pointer.
A workaround only for Term::ReadLine::Gnu would be the appended
patch. It makes sure that LINES and COLUMNS are defined in the
environment before initializing the GNU Readline Library, so that
putenv() hopefully doesn't need to modify the char **environ.
Please keep in mind that this patch is only a workaound for the weak
assumption in my_setenv().
Kind regards,
Joerg
--
Gaertner Datensysteme 38114 Braunschweig
Joerg Schumacher Hamburger Str. 273a
Tel: 0531-2335555 Fax: 0531-2335556
----------------------------------------------------------------------
--- Term-ReadLine-Gnu-1.07/Gnu.pm.orig Wed Nov 17 23:22:59 1999
+++ Term-ReadLine-Gnu-1.07/Gnu.pm Wed Nov 17 23:28:26 1999
@@ -159,6 +159,11 @@
# set rl_readline_name before .inputrc is read in rl_initialize()
$Attribs{readline_name} = $name;
+ # make sure that LINES and COLUMNS are defined in the environment
+ # before initializing the GNU Readline Library
+ $ENV{LINES} = 25 if !defined($ENV{LINES});
+ $ENV{COLUMNS} = 80 if !defined($ENV{COLUMNS});
+
# initialize the GNU Readline Library and termcap library
$self->initialize();
----------------------------------------------------------------------
#!/tmp/perl/bin/perl -w
# dumps core if LINES and COLUMNS aren't defined in the env
use Term::ReadLine;
$RL = new Term::ReadLine 'foo';
$ENV{PATH} ="foo";
use vars qw($RL);
----------------------------------------------------------------------
Summary of my perl5 (5.0 patchlevel 5 subversion 3) configuration:
Platform:
osname=solaris, osvers=2.5.1, archname=sun4-solaris
uname='sunos aunt 5.5.1 generic_103640-24 sun4u sparc '
hint=recommended, useposix=true, d_sigaction=define
usethreads=undef useperlio=undef d_sfio=undef
Compiler:
cc='cc', optimize='-O', gccversion=2.7.2.1
cppflags='-I/usr/local/include'
ccflags ='-I/usr/local/include'
stdchar='unsigned char', d_stdstdio=define, usevfork=false
intsize=4, longsize=4, ptrsize=4, doublesize=8
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
alignbytes=8, usemymalloc=n, prototype=define
Linker and Libraries:
ld='cc', ldflags =' -L/usr/local/lib'
libpth=/usr/local/lib /lib /usr/lib /usr/ccs/lib
libs=-lsocket -lnsl -ldb -ldl -lm -lc -lcrypt
libc=/lib/libc.so, so=so, useshrplib=false, libperl=libperl.a
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' '
cccdlflags='-fPIC', lddlflags='-G -L/usr/local/lib'
Characteristics of this binary (from libperl):
Built under solaris
Compiled at Nov 17 1999 23:34:56
@INC:
/tmp/perl/lib/5.00503/sun4-solaris
/tmp/perl/lib/5.00503
/tmp/perl/lib/site_perl/5.005/sun4-solaris
/tmp/perl/lib/site_perl/5.005
.