read file into scalar

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: read file into scalar by Limbic~Region (Chancellor) on Oct 28, 2006 at 15:21 UTC
Anonymous Monk, That is because in scalar context, the angle bracket operator (see also readline) uses $/ (see perlvar) to return a single line. To get it to read the entire file, simply undef it (locally of course). `my $page; { local $/; open(my $fh, '<', $file) or die $!; $page = <$fh>; }` [download] Cheers - L~R	[reply] [d/l]
Re: read file into scalar by davido (Cardinal) on Oct 28, 2006 at 15:33 UTC
`do{...}` is a nice way to encapsulate the process. `my $page = do { local $/; open my $pagefile, '<', $success or die $! <$pagefile>; };` [download] Dave	[reply] [d/l] [select]
Re: read file into scalar by imp (Priest) on Oct 28, 2006 at 15:22 UTC
You can change the special $/ variable to enable 'slurp mode'. `open PAGE, '<', $success or die "Can't open $success : $!"; flock (PAGE, 1) or die "Can't lock $success for reading: $!"; local $/; my $page = <PAGE>; close PAGE;` [download]	[reply] [d/l]
Re: read file into scalar by jdporter (Paladin) on Oct 28, 2006 at 15:46 UTC
I often to this: `my $text = do { local( @ARGV, $/ ) = ( $file ); <> };` [download] although it's not as robust as the other solutions which `die` on error. We're building the house of the future together.	[reply] [d/l]
Re: read file into scalar by arkturuz (Curate) on Oct 28, 2006 at 18:59 UTC
Use File::Slurp. It has everything you need for simple file reading and writing, and the most simplified interface.	[reply]
Re^2: read file into scalar by mickeyn (Priest) on Oct 29, 2006 at 11:35 UTC
follow an advice from 'Perl Best Practices' and use Perl6::Slurp. Enjoy, Mickey	[reply]
Re^3: read file into scalar by arkturuz (Curate) on Oct 30, 2006 at 11:02 UTC
I follow my advice not to mess with unfinished programming languages and to-be-announced features :-) Anyway, thanks for the advice, I'll explore it.	[reply]
Re^2: read file into scalar by ysth (Canon) on Oct 30, 2006 at 18:43 UTC
Everything you need except for locking, which this OP seems to need. Though if a lock isn't needed for the whole read/update data/write cycle, File::Slurp's atomic option may be enough.	[reply]
Re: read file into scalar by tsee (Curate) on Oct 28, 2006 at 18:46 UTC
Hi, perhaps you're doing it just for brevity, but I can't resist pointing out that it's a very bad idea to use flock() with numeric constants (e.g. 1). You should use the Fcntl module and import the flock constants: `use Fcntl qw/:flock/; ... open flock($fh, FLOCK_EX); # or: flock($fh, FLOCK_SH); ...` [download] Aside from being portable, it has the added benefit of being more friendly on the eyes and less demanding to your memory. Steffen	[reply] [d/l]