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Re: stdin/stdout with perl not o.k


<18 Dec 2000, 9:11 Uhr wars, als Charles Wilson folgendes schrub:>
< Re: stdin/stdout with perl not o.k >

> Your script works fine here.
> 
> ~ > ./test.pl
> Are you o.k?[yes/no] yes
> 
> fine...
> 
> 
> cygutils perl-5.6.0
> cygwin-1.1.6-1
> 
> --Chuck

Thank you very much Chuck.

I got a real good hint from Eric.

It is new in perl?
you can set PERLIO=perlio and PERLIO=stdio, i compiled with PERLIO and 
then got this problems, if i set PERLIO=stdio export PERLIO=stdio), it
works fine again, now i know, that it is all o.k. with perl, all o.k.
with cygwin, it depends on type of buffering.

NAME

perlio - perl pragma to configure C level IO

SYNOPSIS

  Shell:
    PERLIO=perlio perl ....

    print "Have ",join(',',keys %perlio::layers),"\n";
    print "Using ",join(',',@perlio::layers),"\n";


DESCRIPTION

Mainly a Place holder for now.

The %perlio::layers hash is a record of the available ``layers'' that
may be pushed onto a PerlIO stream.

The @perlio::layers array is the current set of layers that are used
when a new PerlIO stream is opened. The C code looks are the array each
time a stream is opened so the ``stack'' can be manipulated by messing
with the array :

    pop(@perlio::layers);
    push(@perlio::layers,$perlio::layers{'stdio'});

The values if both the hash and the array are perl objects, of class
perlio::Layer which are created by the C code in perlio.c. As yet there
is nothing useful you can do with the objects at the perl level.

There are three layers currently defined:

unix
     Low level layer which calls read, write and lseek etc. 

stdio
     Layer which calls fread, fwrite and fseek/ftell etc. Note that as
	 this is ``real'' stdio it will ignore any layers beneath it and
     got straight to the operating system via the C library as usual. 

perlio
     This is a re-implementation of ``stdio-like'' buffering written as
     a PerlIO ``layer''. As such it will call whatever layer is below
     it for its operations. 

Defaults and how to override them

If Configure found out how to do ``fast'' IO using system's stdio, then
 the default layers are :

  unix stdio

Otherwise the default layers are

  unix perlio

(STDERR will have just unix in this case as that is optimal way to make
 it ``unbuffered'' - do not add a buffering layer!)

The default may change once perlio has been better tested and tuned.

The default can be overridden by setting the environment variable
PERLIO to a space separated list of layers (unix is always pushed
first). This can be used to see the effect of/bugs in the various
layers e.g.

  cd .../perl/t
  PERLIO=stdio  ./perl harness
  PERLIO=perlio ./perl harness


AUTHOR

Nick Ing-Simmons <nick@ing-simmons.net>
-- 
=^..^=
Gerrit Peter Haase

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