print from a Regular Expression, repeating lines

[mrlambdin]

I have an archive file that has 300+ archives in this format

____________________________________________________
Archive[0]: d:\archives\piarch.012 (500MB, Used: 9.0%)
PIarcfilehead[$Workfile: piarfile.cxx $ $Revision: 114 $]::
Version: 5 Path: d:\archives\piarch.012
State: 4 Type: 0 (fixed) Write Flag: 1 Shift Flag: 1
Record Size: 1024 Count: 512000 Add Rate/Hour: 4118.3
Offsets: Primary: 25853/128000 Overflow: 491596/512000
Start Time: 1-Apr-08 22:02:38
End Time: Current Time
Backup Time: 2-Apr-08 02:01:07
______________________________________________________

and I need to extract the "Archive[x]... Start Time:... End Time:.... lines, printed on (1) SINGLE line

expected output: "Archive[x]...Start Time:...End Time:...


here's my code:

my $m1;
my $m2;

$filename = "PIDATA";

open( FILE, "< $filename" ) or die "Can't open $filename: $!";

print "PI Archive Record Extraction.\n";
print "Matthew R. Lambdin\n";
print "______________________________________________________\n";

while(<FILE>){

chomp;

if(/^\s*Archive\[\d+\].*/){
        $m1 =~ $_;
}

if(/^\s*Start\s+Time.*/){
        $m2 =~ $_;
}

if(/^\s*End\s+Time.*/){
        print "$m1 ...$m2 ...$_\n";
}
}

When I run this, it prints out: " ... ... End Time: " meaning, only the 3rd regular expression gets printed. Why won't the first and second Regular Expression print? all I get is a space.

Thank you in advance.

 

[plunkett]

change $m1 =~ $_; etc to $m1 = $_;

so use "=" instead of "=~"

 

[KevinADC]

If all you want to do is print the records:

my $filename = "PIDATA";

open( FILE, "< $filename" ) or die "Can't open $filename: $!";

print "PI Archive Record Extraction.\n";
print "Matthew R. Lambdin\n";
print "______________________________________________________\n";

while(<FILE>){

chomp;

if(/^\s*Archive\[\d+\].*/){
        print "$_ ";
}

if(/^\s*Start\s+Time.*/){
        print "$_ ";
}

if(/^\s*End\s+Time.*/){
        print "$_\n";
}
}

------------------------------------------
- Kevin, perl coder unexceptional!

 

[KevinADC]

actually the 'if' conditions are better written as if/elsif conditions:

if(/^\s*Archive\[\d+\].*/){
        print "$_ ";
}

elsif(/^\s*Start\s+Time.*/){
        print "$_ ";
}

elsif(/^\s*End\s+Time.*/){
        print "$_\n";
}

otherwise perl will evaluate all of the regexps instead of stopping when it finds the correct one.

------------------------------------------
- Kevin, perl coder unexceptional!

 

[mrlambdin]

I changed the code to the last reply, and my output is:

Archive[0]: d:\archives\piarch.012 (500MB, Used: 9.0%)
Start Time: 1-Apr-08 22:02:38
End Time: Current Time


I thought "chomp" would remove the extra whitespace and the result would be printed all on ONE line?

 

[stevexff]

chomp removes the newline at the end of the data, if there is one. What constitutes a newline depends on which operating system you use. Things can go awry if the file was created on say a Unix box, and you are reading it on Windows or a Mac.

Steve

[small]"Every program can be reduced by one instruction, and every program has at least one bug. Therefore, any program can be reduced to one instruction which doesn't work." (Object:erlDesignPatterns)[/small]

 

[mrlambdin]

I copied the output into MS Word, and found each line had a "newline" entered, which explains why the output is printing this way... Does PERL have a command to remove formatting of a text file before extracting data?

 

[brigmar]

All you need to do is alter Kevin's suggestion to use capturing...

if(/^\s*(Archive\[\d+\].*)\s*$/){
        print "$1 ";
}

elsif(/^\s*(Start\s+Time.*)\s*$/){
        print "$1 ";
}

elsif(/^\s*(End\s+Time.*)\s*$/){
        print "$1\n";
}

The 'stuff inside' the ()'s is captured into '$1'
If there was a second set of parentheses, the stuff inside them would be captured into $2.
And so on.