copy everything before the first blank line - perl

Question

I have a file with several blocks of text separated by blank line. Ex.:
block1
block1
block2
block3
block3
I need a solution with sed, awk or Perl to locate the first blank line and redirect the previous block to another file and so on until the end of the file.
I have this command in sed that locates the first block, but not the rest:
sed -e '/./!Q'
Can someone help me?

Answer 1

give this line a try:
awk -v RS="" '{print > "file"++c".txt"}' input
it will generate file1...n.txt

Answer 2

Here's an awk:
$ awk 'BEGIN{file="file"++cont}/^$/{file="file"++cont;next}{print>file}' infile
Results
$ cat file1
block1
block1
$ cat file2
block2
$ cat file3
block3
block3

Answer 3

taking into account several empty string between block
awk '/./{if(!L)++C;print>"Out"C".txt"}{L=$0!~/^$/}' YourFile
Sed will not allow different external files (unspecified number of in fact) as output

Answer 4

Here's the solution in Perl
open( my $fh, '<', '/tmp/a.txt' ) or die $!;
{
## record delimiter
local $/ = "\n\n";
my $count = 1;
while ( chomp( my $block = <$fh> ) ) {
open( my $ofh, '>', sprintf( '/tmp/file%d', $count++ ) ) or die $!;
print {$ofh} $block;
close($ofh);
}
}
close($fh);

Answer 5

Here's my solution in Perl:
#!/usr/bin/perl
use strict;
use warnings;
my $n = 0;
my $block = '';
while (<DATA>) { # line gets stored in $_
if (/^\s*$/) { # blank line
write_to_file( 'file' . ++$n, $block );
$block = '';
} else {
$block .= $_;
}
}
# Write any remaining lines
write_to_file( 'file' . ++$n, $block );
sub write_to_file {
my $file = shift;
my $data = shift;
open my $fh, '>', $file or die $!;
print $fh $data;
close $fh;
}
__DATA__
block1
block1
block2
block3
block3
Output:
$ grep . file*
file1:block1
file1:block1
file2:block2
file3:block3
file3:block3

Answer 6

Another way to do it in Perl:
#!/usr/bin/perl
use strict;
use warnings;
# store all lines in $data
my $data = do { local $/; <DATA> };
my #blocks = split /\n\n/, $data;
my $n = 0;
write_to_file( 'file' . ++$n, $_ ) for #blocks;
sub write_to_file {
my $file = shift;
my $data = shift;
open my $fh, '>', $file or die $!;
print $fh $data;
close $fh;
}
__DATA__
block1
block1
block2
block3
block3

Answer 7

This might work for you (GNU csplit & sed):
csplit -qf uniqueFileName file '/^$/' '{*}' && sed -i '/^$/d' uniqueFileName*
or if you want to go with the defaults:
csplit -q file '/^$/' '{*}' && sed -i '/^$/d' xx*
Use:
tail -n+1 xx* # to check the results