You can use the backtics to execute your external program and capture its stdout and stderr. By default the backticks discard the stderr and return only the stdout of the external program.So $output = `cmd`; Will capture the stdout of the program cmd and discard stderr. To capture only stderr you can use the shell’s … Read more
First off, a subroutine isn’t passed the @ARGV array. Rather all the parameters passed to a subroutine are flattened into a single list represented by @_ inside the subroutine. The @ARGV array is available at the top-level of your script, containing the command line arguments passed to you script. Now, in Perl, when you call … Read more
You should have tried your hunch. That’s how to do it. my $first = (split /\./, “hello.world”)[0]; You could use a list-context assignment that grabs the first field only. my($first) = split /\./, “hello.world”; To print it, use print +(split /\./, “hello.world”)[0], “\n”; or print ((split(/\./, “hello.world”))[0], “\n”); The plus sign is there because of … Read more
If I understand you, perhaps you don’t need an array of zeroes; rather, you need a hash. The hash keys will be the values in the other array and the hash values will be the number of times the value exists in the other array: use strict; use warnings; my @other_array = (0,0,0,1,2,2,3,3,3,4); my %tallies; … Read more
Quick shell one-liner: perl -le ‘print scalar localtime 1357810480;’ Thu Jan 10 10:34:40 2013 Or, if you happen to have the timestamps in a file, one per line: perl -lne ‘print scalar localtime $_;’ <timestamps
You can just do it. { local @ARGV = qw<param1 param2 param3>; do ‘/home/buddy/myscript.pl’; } Prevents the overhead of loading in another copy of perl.
Please remember the rules of Optimization Club: The first rule of Optimization Club is, you do not Optimize. The second rule of Optimization Club is, you do not Optimize without measuring. If your app is running faster than the underlying transport protocol, the optimization is over. One factor at a time. No marketroids, no marketroid … Read more
I put your C++ function into header file as an inline function for testing. I was then able to construct a SWIG interface that does what you are looking for. It has two key parts. Firstly I wrote a typemap that will allow either a std::map, or a perl hash to be given as input … Read more
After playing around with this, I’m satisfied that what I said in the question is right. Each call to (?PARNO) gets a complete and separate set of the match variables that it discards at the end of its run. You can get all the things that matched in each sub pattern by using an array … Read more
The standard way for telling what type of object you have is either ref or Scalar::Util::blessed. If you know the object is blessed, then they return the same information. my $class1 = blessed( $obj ); my $class2 = ref $obj; But ref will also return ‘HASH’ for unblessed hashes, while blessed refuses to play that … Read more