FAQ 5.11 How can I write() into a string?

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5.11: How can I write() into a string?


See "Accessing Formatting Internals" in perlform for an swrite()
function.



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Re: FAQ 5.11 How can I write() into a string?

On 2007-10-11 07:03, PerlFAQ Server wrote:
> 5.11: How can I write() into a string?
>
>
> See "Accessing Formatting Internals" in perlform for an swrite()
> function.
>

I think a more useful companion question would be

How can I open a file handle to a string?

Use open(my $fh, '>', \$string); or open(my $fh, '<', \$string);

If this is in the FAQ I haven't found it.

hp


--
_ | Peter J. Holzer | I know I'd be respectful of a pirate
|_|_) | Sysadmin WSR | with an emu on his shoulder.
| | | hjp@hjp.at |
__/ | http://www.hjp.at/ | -- Sam in "Freefall"

Re: FAQ 5.11 How can I write() into a string?

Quoth "Peter J. Holzer" :
> On 2007-10-11 07:03, PerlFAQ Server wrote:
> > 5.11: How can I write() into a string?
> >
> > See "Accessing Formatting Internals" in perlform for an swrite()
> > function.
>
> I think a more useful companion question would be
>
> How can I open a file handle to a string?
>
> Use open(my $fh, '>', \$string); or open(my $fh, '<', \$string);

With reference to IO::String for pre-5.8 perls?

Ben

Re: FAQ 5.11 How can I write() into a string?

On Sat, 27 Oct 2007 12:54:59 +0200, "Peter J. Holzer"
wrote:

>I think a more useful companion question would be
>
> How can I open a file handle to a string?
>
> Use open(my $fh, '>', \$string); or open(my $fh, '<', \$string);

I second that.


Michele
--
{$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
(($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^ ..'KYU;*EVH[.FHF2W+#"\Z*5TI/ER 256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,

Re: FAQ 5.11 How can I write() into a string?

On 2007-10-27 11:52, Ben Morrow wrote:
>
> Quoth "Peter J. Holzer" :
>> On 2007-10-11 07:03, PerlFAQ Server wrote:
>> > 5.11: How can I write() into a string?
>> >
>> > See "Accessing Formatting Internals" in perlform for an swrite()
>> > function.
>>
>> I think a more useful companion question would be
>>
>> How can I open a file handle to a string?
>>
>> Use open(my $fh, '>', \$string); or open(my $fh, '<', \$string);
>
> With reference to IO::String for pre-5.8 perls?

Yup. Something like this:

------------------------------------------------------------ ------------
How can I open a file handle to a string?

Since Perl 5.8.0, you can pass a reference to a scalar instead of
the filename to create a file handle which can be used to read of
write the string:

open(my $fh, '>', \$string) or die ...
print $fh "foo\n";
print $fh "bar\n"; # $string now contains "foo\nbar\n"

open(my $fh, '<', \$string) or die ...
my $x = <$fh>; # $x now contains "foo\n"

With older perls the IO::String module provides similar
functionality.
------------------------------------------------------------ ------------

hp



--
_ | Peter J. Holzer | It took a genius to create [TeX],
|_|_) | Sysadmin WSR | and it takes a genius to maintain it.
| | | hjp@hjp.at | That's not engineering, that's art.
__/ | http://www.hjp.at/ | -- David Kastrup in comp.text.tex

Re: FAQ 5.11 How can I write() into a string?

In article , Peter J. Holzer
wrote:

> On 2007-10-11 07:03, PerlFAQ Server wrote:
> > 5.11: How can I write() into a string?
> >
> >
> > See "Accessing Formatting Internals" in perlform for an swrite()
> > function.
> >
>
> I think a more useful companion question would be
>
> How can I open a file handle to a string?

That would be a good question, although you might want to phrase is
"How do I print to a string instead of a file?".

If someone writes out the full answer, I'll add it to the FAQ. Please
send the answer to perlfaq-workers as noted in perlfaq.pod.

Thanks, :)

Re: FAQ 5.11 How can I write() into a string?

In article <271020071417420054%brian.d.foy@gmail.com>, brian d foy
wrote:

> In article , Peter J. Holzer
> wrote:

> > How can I open a file handle to a string?


> If someone writes out the full answer, I'll add it to the FAQ. Please
> send the answer to perlfaq-workers as noted in perlfaq.pod.

Oh, never mind. Peter already posted an answer. I've added that to the
FAQ.

Thanks, :)

Re: FAQ 5.11 How can I write() into a string?

brian d foy wrote:
> In article , Peter J. Holzer
> wrote:
>
>> On 2007-10-11 07:03, PerlFAQ Server wrote:
>>> 5.11: How can I write() into a string?
>>>
>>>
>>> See "Accessing Formatting Internals" in perlform for an swrite()
>>> function.
>>>
>>
>> I think a more useful companion question would be
>>
>> How can I open a file handle to a string?
>
> That would be a good question, although you might want to phrase is
> "How do I print to a string instead of a file?".

Well, isn't the answer to that question a simple:

Use the sprintf() function?

jue

Re: FAQ 5.11 How can I write() into a string?

On Sat, 27 Oct 2007 19:48:39 GMT, "Jürgen Exner"
wrote:

>> That would be a good question, although you might want to phrase is
>> "How do I print to a string instead of a file?".
>
>Well, isn't the answer to that question a simple:
>
> Use the sprintf() function?

No, that's the answer to "How do I printf to a string instead of a
file?"


Michele
--
{$_=pack'B8'x25,unpack'A8'x32,$a^=sub{pop^pop}->(map substr
(($a||=join'',map--$|x$_,(unpack'w',unpack'u','G^ ..'KYU;*EVH[.FHF2W+#"\Z*5TI/ER 256),7,249);s/[^\w,]/ /g;$ \=/^J/?$/:"\r";print,redo}#JAPH,

Re: FAQ 5.11 How can I write() into a string?

On 2007-10-27 19:17, brian d foy wrote:
> In article , Peter J. Holzer
> wrote:
>>
>> How can I open a file handle to a string?
>
> That would be a good question, although you might want to phrase is
> "How do I print to a string instead of a file?".

That was my first idea, too. I changed it because it works for
reading a string as well as writing.

> Thanks, :)

You're welcome.

hp


--
_ | Peter J. Holzer | It took a genius to create [TeX],
|_|_) | Sysadmin WSR | and it takes a genius to maintain it.
| | | hjp@hjp.at | That's not engineering, that's art.
__/ | http://www.hjp.at/ | -- David Kastrup in comp.text.tex