[perl #24496] Exploiting PerlIO "feature" with trepidation

# New Ticket Created by  Richard Kandarian 
# Please include the string:  [perl #24496]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt2/Ticket/Display.html?id=24496 >



This is a bug report for perl from richard.kandarian@lanl.gov,
generated with the help of perlbug 1.34 running under perl v5.8.0.


-----------------------------------------------------------------
[Please enter your report here]

I'm working on Win32, but intending to be able to run on *nix also.

I'm embedding perl in a COTS (Commercial Off The Shelf) application via
an API. My embedded perl is loaded into the application as a DLL. I
found that My embedded perl had no access to stdout or stderr in the
COTS application.

On perusing the Perl source code I (happily) found that PerlIO is lazily
setup giving me an opportunity to open a file for stdout and stderr for
perl to discover and blissfully use. This is VERY handy.

My wish is that this be acknowledged as a USEFUL FEATURE and not changed
in future releases.

Please also notice my use of rsignal in the attached code snippet.

Code snippets follow: (Any comments and/or advice will be much
appreciated.  Especially as it looks very promising that my application
will be released under the "Artistic License" soon.)

   ....
   perl_construct( my_perl);
   /*
   I use plain ol' stdio when there is no perl interpreter, and I
   save stdio stuff prior to including perl .h files as pperl_*
   */
   pperl_fflush(NULL);
   open_properl_stdio(); /* see below */
   /*
    Needed on Win32 to catch WM_TIMER that I seem intercept because of
    something the host app does.
    */
   rsignal(14, pp_sigcheck);
   pperl_no_interp = 0; /* To tell my what kind of IO to use */
   ... /* opening debugging log files & such for use with PerlIO */
   exitstatus = perl_parse(my_perl, xs_init, PPargc, PPargv, (char**)NULL);
   ...
   /* after killing the interpreter */
   PerlIO_close(PerlIO_stdout());
   PerlIO_close(PerlIO_stderr());
   ...


/* Re-direct stdout and stderr to log files */
void open_properl_stdio(){
   int outfd, errfd;
#if defined _WIN32
#define TEXTMODE "t"
   HANDLE h;
   if((h = CreateFile("properl.out", GENERIC_WRITE, FILE_SHARE_READ, NULL,
     TRUNCATE_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL)) ==
     INVALID_HANDLE_VALUE){
     if((h = CreateFile("properl.out", GENERIC_WRITE, FILE_SHARE_READ, NULL,
       CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL)) ==
       INVALID_HANDLE_VALUE){
       pperl_fprintf(pperl_stderr, "Failed to open properl.out\n");
       exit(1);
     }
   }
   if((outfd = _open_osfhandle(h, 0)) < 0){
     pperl_fprintf(pperl_stderr, "Failed to get fd for properl.out\n");
     exit(1);
   }
   if((h = CreateFile("properl.err", GENERIC_WRITE, FILE_SHARE_READ, NULL,
     TRUNCATE_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL)) ==
     INVALID_HANDLE_VALUE){
     if((h = CreateFile("properl.err", GENERIC_WRITE, FILE_SHARE_READ, NULL,
       CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL)) ==
       INVALID_HANDLE_VALUE){
       pperl_fprintf(pperl_stderr, "Failed to open properl.err\n");
       exit(1);
     }
   }
   if((errfd = _open_osfhandle(h, 0)) < 0){
     pperl_fprintf(pperl_stderr, "Failed to get fd for properl.err\n");
     exit(1);
   }
#else
#define TEXTMODE ""
   if((outfd = open("properl.out", O_CREAT, S_IREAD | S_IWRITE)) < 0){
     pperl_fprintf(pperl_stderr, "Failed to open properl.out\n");
     exit(1);
   }
   if((errfd = open("properl.err", O_CREAT, S_IREAD | S_IWRITE)) < 0){
     pperl_fprintf(pperl_stderr, "Failed to open properl.err\n");
     exit(1);
   }
#endif
   PerlIO_allocate(my_perl);
   PerlIO_fdopen(0, "Ir" "t");
   PerlIO_fdopen(outfd, "Iw" TEXTMODE);
   PerlIO_fdopen(errfd, "Iw" TEXTMODE);
#if 1
   /*
    It might be nice to be able to use tail -f on these...
    But there will be a performance penalty...
    This is not "autoflush" - it will not flush lines with out an \n at
    the end. I haven't figured out how to do that, but this is probably
    good enough.
    */
   PerlIO_setlinebuf(PerlIO_stdout());
   PerlIO_setlinebuf(PerlIO_stderr());
#endif
}

Signal_t pp_sigcheck(int sig){
   PerlIO_printf(PerlIO_stderr(), "Caught signal %d\n", sig);
}


[Please do not change anything below this line]
-----------------------------------------------------------------
---
Flags:
     category=core
     severity=wishlist
---
Site configuration information for perl v5.8.0:

Configured by 085598 at Mon Oct 27 17:00:47 2003.

Summary of my perl5 (revision 5 version 8 subversion 0) configuration:
   Platform:
     osname=MSWin32, osvers=4.0, archname=MSWin32-x86-multi
     uname=''
     config_args='undef'
     hint=recommended, useposix=true, d_sigaction=undef
     usethreads=undef use5005threads=undef useithreads=undef 
usemultiplicity=define
     useperlio=define d_sfio=undef uselargefiles=undef usesocks=undef
     use64bitint=undef use64bitall=undef uselongdouble=undef
     usemymalloc=n, bincompat5005=undef
   Compiler:
     cc='cl', ccflags ='-nologo -Gf -W3 -Od -MD -DNDEBUG -DWIN32 -D_CONSOLE 
-DNO_STRICT -DHAVE_DES_FCRYPT  -DPERL_IMPLICIT_CONTEXT -DUSE_PERLIO 
-DPERL_MSVCRT_READFIX',
     optimize='-Od -MD -DNDEBUG',
     cppflags='-DWIN32'
     ccversion='', gccversion='', gccosandvers=''
     intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
     d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
     ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', 
lseeksize=4
     alignbytes=8, prototype=define
   Linker and Libraries:
     ld='link', ldflags ='-nologo -nodefaultlib 
-release  -libpath:"c:\perl\5.8.0\lib\MSWin32-x86-multi\CORE"  -machine:x86'
     libpth=\lib
     libs=c:\src\openssl-0.9.6c\out32\libeay32.lib  oldnames.lib 
kernel32.lib user32.lib gdi32.lib winspool.lib  comdlg32.lib advapi32.lib 
shell32.lib ole32.lib oleaut32.lib  netapi32.lib uuid.lib wsock32.lib 
mpr.lib winmm.lib  version.lib odbc32.lib odbccp32.lib msvcrt.lib
     perllibs=c:\src\openssl-0.9.6c\out32\libeay32.lib  oldnames.lib 
kernel32.lib user32.lib gdi32.lib winspool.lib  comdlg32.lib advapi32.lib 
shell32.lib ole32.lib oleaut32.lib  netapi32.lib uuid.lib wsock32.lib 
mpr.lib winmm.lib  version.lib odbc32.lib odbccp32.lib msvcrt.lib
     libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl58.lib
     gnulibc_version='undef'
   Dynamic Linking:
     dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
     cccdlflags=' ', lddlflags='-dll -nologo -nodefaultlib 
-release  -libpath:"c:\perl\5.8.0\lib\MSWin32-x86-multi\CORE"  -machine:x86'

Locally applied patches:


---
@INC for perl v5.8.0:
     c:/Pro_Perl/blib/lib
     c:/Pro_Perl/blib/arch
     c:/Perl/5.8.0/lib/MSWin32-x86-multi
     c:/Perl/5.8.0/lib
     c:/Perl/site/5.8.0/lib/MSWin32-x86-multi
     c:/Perl/site/5.8.0/lib
     c:/Perl/site/lib
     .

---
Environment for perl v5.8.0:
     HOME=C:\cygwin\home\085598
     LANG (unset)
     LANGUAGE (unset)
     LD_LIBRARY_PATH (unset)
     LOGDIR (unset)
     PATH=C:\cygwin\usr\local\bin;C:\cygwin\bin;C:\cygwin\bin;c:\Program 
Files\Microsoft Visual Studio .NET\Common7\IDE;c:\Program Files\Microsoft 
Visual Studio .NET\VC7\BIN;c:\Program Files\Microsoft Visual Studio 
.NET\Common7\Tools;c:\Program Files\Microsoft Visual Studio 
.NET\Common7\Tools\bin\prerelease;c:\Program Files\Microsoft Visual Studio 
.NET\Common7\Tools\bin;c:\Program Files\Microsoft Visual Studio 
.NET\FrameworkSDK\bin;c:\WINDOWS\Microsoft.NET\Framework\v1.0.3705;c:\Perl\5.8.0\bin;c:\Perl\5.8.0\bin\MSWin32-x86-multi;c:\Program 
Files\Reflection;c:\WINDOWS\system32;c:\WINDOWS;c:\WINDOWS\System32\Wbem;c:\PROGRA~1\F-Secure\Ssh;c:\Program 
Files\Common Files\Adaptec 
Shared\System;c:\pro_e\proiclient\bin;c:\pro_e\ver23\bin;c:\pro_e\ptchelp2001\bin;c:\pro_e\wildfire\bin;c:\pro_e\mechwildfire\bin;c:\pro_e\ptchelpWildfire\bin
     PERL5LIB=c:/Pro_Perl/blib/lib;c:/Pro_Perl/blib/arch
     PERL_BADLANG (unset)
     SHELL (unset)



Richard Kandarian
http://www.lanl.gov/cgi-bin/fonelink.pl/085598
Any opinions stated in this message are not expressed on behalf of any 
individual or entity other than me unless explicitly noted otherwise. My 
node in the Web: http://www.kandarian.com

• [perl #24496] Exploiting PerlIO "feature" with trepidation by Richard Kandarian