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How do I create an array from a file using every 3rd line


 
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Top Forums Shell Programming and Scripting How do I create an array from a file using every 3rd line
# 15  
Old 08-06-2009
Quote:
Originally Posted by BRH
...
One question: I'm not familiar with perl, if the _DATA_ is an external file, how do I reference it in the script?
...
Let's assume your data is in a file called "data.txt".

Code:
$
$ cat data.txt
ceName: Node-1
processName: tzMgmt
Status: PROCESS_NOT_RUNNING
ceName: Node-2
processName: tzMgmt
Status: PROCESS_RUNNING
ceName: Node-1
processName: XDM
Status: PROCESS_NOT_RUNNING
ceName: Node-2
processName: XDM
Status: PROCESS_RUNNING
$

Then the file handle in the "procheck" script could be changed to "<>", if you pass the data stream to "procheck".

So, "procheck" now looks like this -

Code:
$
$ cat procheck
#!/usr/bin/perl
my %hash;
local $/="RUNNING";
while(<>){
    if(/ceName: ([^ \n]*).*processName: ([^ \n]*).*Status: ([^ \n]*)/ms){
        $hash{$2}->{$1}=$3;
    }
}
print "processName        Status Node-1                   Status Node-2\n";
print "-----------        -------------------              -------------------\n";
foreach my $key (keys %hash){
    print $key,"  ";
    foreach my $k(keys %{$hash{$key}}){
        print $hash{$key}->{$k},"   ";
    }
    print "\n";
}
$
$

Note the change in red color.

And you run the script thusly -

Code:
$
$ # Method 1
$
$ cat data.txt | ./procheck
processName        Status Node-1                   Status Node-2
-----------        -------------------              -------------------
tzMgmt  PROCESS_NOT_RUNNING   PROCESS_RUNNING
XDM  PROCESS_NOT_RUNNING   PROCESS_RUNNING
$
$
$ # Method 2
$
$ ./procheck < data.txt
processName        Status Node-1                   Status Node-2
-----------        -------------------              -------------------
tzMgmt  PROCESS_NOT_RUNNING   PROCESS_RUNNING
XDM  PROCESS_NOT_RUNNING   PROCESS_RUNNING
$
$

Alternatively, if you do not want to pass the data from your file (via pipe or redirection), then you'll have to open the file explicitly in your script.

Assuming the file "data.txt" is in the same directory as "procheck", you'd have this -

Code:
$
$ cat procheck
#!/usr/bin/perl
my %hash;
local $/="RUNNING";
open(INPUT, "data.txt") or die "Can't open data.txt: $!";   # open the file for reading
while(<INPUT>) {                                            # loop through the records
    if(/ceName: ([^ \n]*).*processName: ([^ \n]*).*Status: ([^ \n]*)/ms){
        $hash{$2}->{$1}=$3;
    }
}
print "processName        Status Node-1                   Status Node-2\n";
print "-----------        -------------------              -------------------\n";
foreach my $key (keys %hash){
    print $key,"  ";
    foreach my $k(keys %{$hash{$key}}){
        print $hash{$key}->{$k},"   ";
    }
    print "\n";
}
close(INPUT) or die "Can't close data.txt: $!";             # done; close the file now
$
$ ./procheck
processName        Status Node-1                   Status Node-2
-----------        -------------------              -------------------
tzMgmt  PROCESS_NOT_RUNNING   PROCESS_RUNNING
XDM  PROCESS_NOT_RUNNING   PROCESS_RUNNING
$
$

HTH,
tyler_durden
# 16  
Old 08-07-2009
Quote:
Originally Posted by durden_tyler
Alternatively, if you do not want to pass the data from your file (via pipe or redirection), then you'll have to open the file explicitly in your script.

Assuming the file "data.txt" is in the same directory as "procheck", you'd have this -

Code:
$
$ cat procheck
#!/usr/bin/perl
my %hash;
local $/="RUNNING";
open(INPUT, "data.txt") or die "Can't open data.txt: $!";   # open the file for reading
while(<INPUT>) {                                            # loop through the records
    if(/ceName: ([^ \n]*).*processName: ([^ \n]*).*Status: ([^ \n]*)/ms){
        $hash{$2}->{$1}=$3;
    }
}
print "processName        Status Node-1                   Status Node-2\n";
print "-----------        -------------------              -------------------\n";
foreach my $key (keys %hash){
    print $key,"  ";
    foreach my $k(keys %{$hash{$key}}){
        print $hash{$key}->{$k},"   ";
    }
    print "\n";
}
close(INPUT) or die "Can't close data.txt: $!";             # done; close the file now
$
$ ./procheck
processName        Status Node-1                   Status Node-2
-----------        -------------------              -------------------
tzMgmt  PROCESS_NOT_RUNNING   PROCESS_RUNNING
XDM  PROCESS_NOT_RUNNING   PROCESS_RUNNING
$
$

HTH,
tyler_durden

Tyler, you made my day!Smilie The last method without piping or redirection is what I was looking for.

Thanks so much,

Bjoern

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