What's the effect of a null input record separator?

[here]

Given the one-liner:

perl -0ne 'print "$ARGV\n" if [some condition];' *

What effect does the -0 have on each file? I know the values for paragraph mode 00 and file slurp mode 0777, but I can't find a definitive answer on when $/ is set to the null character.

 

[Bjoern Hoehrmann]

* (e-mail address removed) wrote in comp.lang.perl.misc:

Given the one-liner:

perl -0ne 'print "$ARGV\n" if [some condition];' *

What effect does the -0 have on each file? I know the values for
paragraph mode 00 and file slurp mode 0777, but I can't find a
definitive answer on when $/ is set to the null character.

http://search.cpan.org/perldoc?perlvar "Trying to set the record size
to zero or less will cause reading in the (rest of the) whole file."

 

[sybilfriedman]

Given the one-liner:



perl -0ne 'print "$ARGV\n" if [some condition];' *



What effect does the -0 have on each file? I know the values for paragraph mode 00 and file slurp mode 0777, but I can't find a definitive answer on when $/ is set to the null character.

 

[here]

Given the one-liner:



perl -0ne 'print "$ARGV\n" if [some condition];' *



What effect does the -0 have on each file? I know the values for paragraph mode 00 and file slurp mode 0777, but I can't find a definitive answer on when $/ is set to the null character.

########################

So does that mean that -0 on the command line is equivalent to:

undef $/;
while (<>) {
...
}

 

[John W. Krahn]

Given the one-liner:

perl -0ne 'print "$ARGV\n" if [some condition];' *

What effect does the -0 have on each file? I know the values for
paragraph mode 00 and file slurp mode 0777, but I can't find a
definitive answer on when $/ is set to the null character.

$ perl -MO=Deparse -0ne 'print "$ARGV\n" if [some condition];' *
BEGIN { $/ = "\000"; $\ = undef; }
LINE: while (defined($_ = <ARGV>)) {
print "$ARGV\n" if ['condition'->some];
}
-e syntax OK

The value "\0" will be used as the record separator so if you have a
"text" file it is the same as slurp mode but if you have a "binary" file
you will get as many records as there are "\0" characters in the file.


John

 

[Tim McDaniel]

Quoth (e-mail address removed):

* (e-mail address removed) wrote in comp.lang.perl.misc:

Given the one-liner:

perl -0ne 'print "$ARGV\n" if [some condition];' *

What effect does the -0 have on each file? I know the values for
paragraph mode 00 and file slurp mode 0777, but I can't find a
definitive answer on when $/ is set to the null character.

http://search.cpan.org/perldoc?perlvar "Trying to set the record
size to zero or less will cause reading in the (rest of the) whole
file."

Not relevant. That's talking about $/ = \0,

Do you mean
$/ = 0
or is there something special about a scalar reference to 0?