select returns -1 but $! is 0 (or empty string) #11160
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From oskar@osk.mine.nuThis is a bug report for perl from oskar@osk.mine.nu, The program shows how select in some situations fails and return -1 but does not set $!. waitpid=0 select=-1 errno=0 (Sometimes waitpid return >0 in which case this bug is not reproduced. Here is the program - I tried to make it as short as possible. #!/usr/bin/perl -w I did some debugging and it seems the select syscall actually /* compile with gcc -shared -o fake_select.so fake_select.c -fPIC */ #define _GNU_SOURCE int select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout) Regards, Oskar Liljeblad Flags: Site configuration information for perl 5.10.1: Configured by Debian Project at Fri Jan 7 12:14:33 UTC 2011. Summary of my perl5 (revision 5 version 10 subversion 1) configuration: Locally applied patches: @INC for perl 5.10.1: Environment for perl 5.10.1: |
From perl5-porters@ton.iguana.beIn article <rt-3.6.HEAD-28241-1298911559-101.85104-75-0@perl.org>,
This is the annoying result of the way safe signals work. Basically on the However, i don't think you SHOULD have to do this. To my mind perl itself |
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The RT System itself - Status changed from 'new' to 'open' |
From perl5-porters@ton.iguana.beIn article <ikiitc$k2b$1@post.home.lunix>,
And here is a patch that saves ========================================================================== Inline Patch |
From @LeontOn Tue, Mar 1, 2011 at 11:48 AM, Ton Hospel <perl5-porters@ton.iguana.be> wrote:
Actually, blead already does this (see commit Leon |
From @LeontOn Tue, Mar 1, 2011 at 2:29 PM, Ton Hospel <perl5-porters@ton.iguana.be> wrote:
Next time please send a patch against blead, not such an old release Leon |
From perl5-porters@ton.iguana.beIn article <AANLkTimMGcg3qH_8OyShXmiqEcGw9GePTB-butjtRzyy@mail.gmail.com>,
Ah, good. I guess i'll have to start using git to see blead... ...fetching git and a git copy of blead and looking at that commit.... But actually I like my patch (in this same thread) slightly better. Ps: why is the function called Perl_despatch_signals instead of |
From perl5-porters@ton.iguana.beIn article <AANLkTimprXWyhpLz+nRs_Cx2ZYw9tsgCrwDfUVAm7EHD@mail.gmail.com>,
Ok following is the patch against blead. Changes: I have no system where mg.c | 29 ++++++++++++++++++++++++++++- Inline Patchdiff --git a/mg.c b/mg.c
index 7b5fdf5..9f892a3 100644
--- a/mg.c
+++ b/mg.c
@@ -1446,11 +1446,30 @@ void
Perl_despatch_signals(pTHX)
{
dVAR;
+ dSAVEDERRNO;
int sig;
+
+ /* Save $^E by Duplicating some code from Perl_magic_get and Perl_magic_set
+ VAX and unix are already handled by SAVED ERRNO */
+#if defined(MACOS_TRADITIONAL)
+ const short saved_err = gMacPerl_OSErr;
+#elif defined(OS2)
+ int saved_err;
+
+ if ((_emx_env & 0x200) && errno != errno_isOS2) {
+ const int tmp = _syserrno();
+ if (tmp) /* 2nd call to _syserrno() makes it 0 */
+ Perl_rc = tmp;
+ }
+ saved_err = Perl_rc;
+#elif defined(WIN32)
+ const DWORD saved_err = GetLastError();
+#endif
+
+ SAVE_ERRNO;
PL_sig_pending = 0;
for (sig = 1; sig < SIG_SIZE; sig++) {
if (PL_psig_pend[sig]) {
- dSAVE_ERRNO;
#ifdef HAS_SIGPROCMASK
/* From sigaction(2) (FreeBSD man page):
* | Signal routines normally execute with the signal that
@@ -1484,6 +1503,14 @@ Perl_despatch_signals(pTHX)
LEAVE;
#endif
RESTORE_ERRNO;
+#if defined(MACOS_TRADITIONAL)
+ gMacPerl_OSErr = saved_err;
+#elif defined(OS2)
+ Perl_rc = saved_err;
+ os2_setsyserrno(Perl_rc);
+#elif defined(WIN32)
+ SetLastError(saved_err);
+#endif
}
}
}
--
1.7.1 |
From @cpansproutOn Tue Mar 01 07:44:37 2011, perl5-porters@ton.iguana.be wrote:
Your patch uses MACOS_TRADITIONAL. Mac Classic support was removed from
|
From @tonycozOn Tue Mar 01 07:44:37 2011, perl5-porters@ton.iguana.be wrote:
While the patch supplied has some issues, I wonder if dSAVE_ERRNO should Tony |
From @tonycozOn Sun Jun 23 22:50:30 2013, tonyc wrote:
Here's an alternate patch that extends the errno save macros for No tests yet. Tony |
From @tonycoz0001-perl-85104-work-harder-to-save-error-numbers.patchFrom 2b38ee36b8f61351702be32738a3316707bf1c35 Mon Sep 17 00:00:00 2001
From: Tony Cook <tony@develop-help.com>
Date: Mon, 15 Jul 2013 10:42:01 +1000
Subject: [PATCH] [perl #85104] work harder to save error numbers
Updates the errno save macros to save the platform error number where
needed for more than just VMS.
The OS/2 code is untested.
---
perl.h | 31 +++++++++++++++++++++++++------
1 file changed, 25 insertions(+), 6 deletions(-)
diff --git a/perl.h b/perl.h
index bc8388f..a745c2b 100644
--- a/perl.h
+++ b/perl.h
@@ -1168,12 +1168,6 @@ EXTERN_C char *crypt(const char *, const char *);
# define SS_IVCHAN SS$_IVCHAN
# define SS_NORMAL SS$_NORMAL
#else
-# define SETERRNO(errcode,vmserrcode) (errno = (errcode))
-# define dSAVEDERRNO int saved_errno
-# define dSAVE_ERRNO int saved_errno = errno
-# define SAVE_ERRNO (saved_errno = errno)
-# define RESTORE_ERRNO (errno = saved_errno)
-
# define LIB_INVARG 0
# define RMS_DIR 0
# define RMS_FAC 0
@@ -1188,6 +1182,31 @@ EXTERN_C char *crypt(const char *, const char *);
# define SS_NORMAL 0
#endif
+#ifdef WIN32
+# define dSAVEDERRNO int saved_errno; DWORD saved_win32_errno
+# define dSAVE_ERRNO int saved_errno = errno; DWORD saved_win32_errno = GetLastError()
+# define SAVE_ERRNO ( saved_errno = errno, saved_win32_errno = GetLastError() )
+# define RESTORE_ERRNO ( errno = saved_errno, SetLastError(saved_win32_errno) )
+#endif
+
+#ifdef OS2
+# define dSAVEDERRNO int saved_errno; unsigned long saved_os2_errno
+# define dSAVE_ERRNO int saved_errno = errno; unsigned long saved_os2_errno = Perl_rc
+# define SAVE_ERRNO ( saved_errno = errno, saved_os2_errno = Perl_rc )
+# define RESTORE_ERRNO ( errno = saved_errno, Perl_rc = saved_os2_errno) )
+#endif
+
+#ifndef SETERRNO
+# define SETERRNO(errcode,vmserrcode) (errno = (errcode))
+#endif
+
+#ifndef dSAVEDERRNO
+# define dSAVEDERRNO int saved_errno
+# define dSAVE_ERRNO int saved_errno = errno
+# define SAVE_ERRNO (saved_errno = errno)
+# define RESTORE_ERRNO (errno = saved_errno)
+#endif
+
#define ERRSV GvSVn(PL_errgv)
#define CLEAR_ERRSV() STMT_START { \
--
1.7.10.4
|
From @tonycozOn Sun Jul 14 18:10:49 2013, tonyc wrote:
I've applied a varient of this as Tony |
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@tonycoz - Status changed from 'open' to 'resolved' |
Migrated from rt.perl.org#85104 (status was 'resolved')
Searchable as RT85104$
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