open FILEHANDLE,EXPR open FILEHANDLE,MODE,EXPR open FILEHANDLE,MODE,EXPR,LIST open FILEHANDLE,MODE,REFERENCE open FILEHANDLE Opens the file whose filename is given by EXPR, and associates it with FILEHANDLE. Simple examples to open a file for reading: open(my $fh, "<", "input.txt") or die "cannot open < input.txt: $!"; and for writing: open(my $fh, ">", "output.txt") or die "cannot open > output.txt: $!"; (The following is a comprehensive reference to open(): for a gentler

NAME SYNOPSIS DESCRIPTION NOTE WARNING Operator Names and Operator Lists Opcode Functions Manipulating Opsets TO DO (maybe) Predefined Opcode Tags SEE ALSO AUTHORS NAME Opcode - Disable named opcodes when compiling perl code SYNOPSIS use Opcode; DESCRIPTION Perl code is always compiled into an internal format before execution. Evaluating perl code (e.g. via "eval" or "do 'file'") causes the code to be compiled into an internal format and then, provided there was no error in the compilation,

oct EXPR oct Interprets EXPR as an octal string and returns the corresponding value. (If EXPR happens to start off with 0x , interprets it as a hex string. If EXPR starts off with 0b, it is interpreted as a binary string. Leading whitespace is ignored in all three cases.) The following will handle decimal, binary, octal, and hex in standard Perl notation: $val = oct($val) if $val =~ /^0/; If EXPR is omitted, uses $_ . To go the other way (produce a number in octal), use sprintf() or printf():

NAME SYNOPSIS DESCRIPTION CONVENTIONS IMPLEMENTATION BUGS AUTHOR NAME O - Generic interface to Perl Compiler backends SYNOPSIS perl -MO=[-q,]Backend[,OPTIONS] foo.pl DESCRIPTION This is the module that is used as a frontend to the Perl Compiler. If you pass the -q option to the module, then the STDOUT filehandle will be redirected into the variable $O::BEGIN_output during compilation. This has the effect that any output printed to STDOUT by BEGIN blocks or use'd modules will be stored in thi

not These operators are documented in perlop.

No-ops Perl doesn't officially have a no-op operator, but the bare constants 0 and 1 are special-cased not to produce a warning in void context, so you can for example safely do 1 while foo();

no MODULE VERSION LIST no MODULE VERSION no MODULE LIST no MODULE no VERSION See the use function, of which no is the opposite.

NAME SYNOPSIS DESCRIPTIONEnforcing redispatch Avoiding repetitions Invoking all versions of a method with a single call Using EVERY methods AUTHOR BUGS AND IRRITATIONS COPYRIGHT NAME NEXT.pm - Provide a pseudo-class NEXT (et al) that allows method redispatch SYNOPSIS use NEXT; package A; sub A::method { print "$_[0]: A method\n"; $_[0]->NEXT::method() } sub A::DESTROY { print "$_[0]: A dtor\n"; $_[0]->NEXT::DESTROY() } package B; use base qw( A ); sub B::AUTOLOAD { print "$

next LABEL next EXPR next The next command is like the continue statement in C; it starts the next iteration of the loop: LINE: while (<STDIN>) { next LINE if /^#/; # discard comments #... } Note that if there were a continue block on the above, it would get executed even on discarded lines. If LABEL is omitted, the command refers to the innermost enclosing loop. The next EXPR form, available as of Perl 5.18.0, allows a label name to be computed at run time, being otherwise iden

NAME SYNOPSIS DESCRIPTION AUTHOR COPYRIGHT NAME Net::Time - time and daytime network client interface SYNOPSIS use Net::Time qw(inet_time inet_daytime); print inet_time(); # use default host from Net::Config print inet_time('localhost'); print inet_time('localhost', 'tcp'); print inet_daytime(); # use default host from Net::Config print inet_daytime('localhost'); print inet_daytime('localhost', 'tcp'); DESCRIPTION Net::Time provides subroutines that obtain the time on a remo