It's the first time I've used a hash in Perl, and I'm stuck in a weird problem. What I'm trying to do is after I backup files in a directory, I use a Perl program to check if all files appearin the log file. So I had the following code:
our (%missing_files) = (); # global definition on the top of the program
... do something ...
sub CheckTarResult {
my (#dir_list) = (); # dir list
my (#file_list) = (); # will be filled with all file names in one dir
my ($j) = "";
my ($k) = ""; # loop variable
my ($errors) = 0; # number of missing files
... do something ...
foreach $j (#dir_list) {
#file_list = `ls $j`;
foreach $k (#file_list) {
$result = `cat $logfile | grep $k`;
if ($result eq "") {
$errors++;
$missing_files{$j} = ${k};
}
}
#file_list = ();
}
... do something ...
my($dir) = "";
my($file) = "";
while ( ($dir, $file) = each(%missing_files) ) {
print $dir . " : " . $file;
}
I made an empty log file to do the test, the expecting result should give me all files missing, but somehow "missing_files" only stores the last missing file in each dir. The logic seems to be straightforward, so what am I missing here?
Edit:
I used the advice from #Borodin, and it worked. But in order to print the content of an array reference, we need to loop through elements in the array. The code after the change looks like the following:
... everything before is the same ...
push #{$missing_files{$j}}, ${k}; # put elements in dictionary
# in the print statement
while( ($dir, $file) = each(%missing_files) ) {
for $i ( 0 .. $#$file ) { # $#$file represents the array size by reference
print $dir . " : " . ${$file}[i];
}
}
Perl hash values can contain only a single scalar. If you want to store a list of things then you must make that scalar an array reference. To do that, change the line
$missing_files{$j} = ${k};
to
push #{$missing_files{$j}}, ${k};
Related
I want to pair two array and add char '/' between them. Let say, two arrays are like below
#array1 = (FileA .. FileZ);
#array2 = (FileA.txt .. FileZ.txt);
The output that I want is like below
../../../experiment/fileA/fileA.txt
.
.
../../../experiment/fileZ/fileZ.txt
here is my code
my #input_name = input();
my $dirname = "../../../experiment/";
# CREATE FOLDER PATH
my #fileDir;
foreach my $input_name (#input_name){
chomp $input_name;
$_ = $dirname . $input_name;
push #fileDir, $_;
}
# CREATE FILE NAME
my #filename;
my $extension = '.txt';
foreach my $input_name (#input_name){
chomp $input_name;
$_ = $input_name . $extension;
push #filename, $_;
}
The code that I'd try is like below. But it seem doesn't work
#CREATE FULL PATH
foreach my $test_path (#test_path){
foreach my $testname (#testname){
my $test = map "$test_path[$_]/$testname[$_]", 0..$#test_path;
push #file, $test;
}
}
print #file;
I assume input() returns something like ('fileA', 'fileB').
The problem with your code is the nested loop here:
foreach my $test_path (#test_path){
foreach my $testname (#testname){
This combines every $test_path with every possible $testname. You don't want that. Also, it doesn't make much sense to assign the result of map to a scalar: All you'll get is the number of elements in the list created by map.
(Also, you have random chomp calls sprinkled throughout your code. None of those should be there.)
You only need a single array and a single loop:
use strict;
use warnings;
sub input {
return ('fileA', 'fileB');
}
my #input = input();
my $dirname = '../../../experiment';
my #files = map "$dirname/$_/$_.txt", #input;
for my $file (#files) {
print "got $file\n";
}
Here the loop is hidden in the map ..., #input call. If you want to write it as a for loop, it would look like this:
my #files;
for my $input (#input) {
push #files, "$dirname/$input/$input.txt";
}
The problem is your algorithm. You're iterating all filenames and all dirnames at the same time.
I mean, your code says "For every directory, create every file".
Try something along the lines of this and you'll be fine:
# WRITE TESTFILE
foreach my $filename (#filename){
chomp $filename;
if ( -e "$filename/$filename" and -d "$filename/$filename" ){
print "File already exists\n";
}
else {
open ( TXT_FILE, ">$filename/$filename" );
print TXT_FILE "Hello World";
close TXT_FILE;
}
}
I have a text file A00010.txt A00011.txt A00012.txt to A00099.txt in myfolder which contains different entries like,
umxwtdn8vtnt_n
umxwtdtnt_nn8v
umxwt_ntdn8vtn
u8vtnt_nmxwtdn
utnt_nmxwtdn8v
my perl code is
#!/usr/bin/perl
use strict;
my $count = 10;
for ($count = 10; $count<= 99; $count++) {
my $result = `/bin/cat /myfolder/A000$count.txt | grep "umxwtdn8vtnt_n"`;
return $result;
}
print $result;
i trying to get $result value but show empty
Is /myfolder really in the root directory? (what do you see in ls /? Do you see myfolder?) It's very rare to add things in the root directory in a Unix system, and I don't think you are messing with /.
Also, you are returning $result outside a subroutine (sub { }), and if that's the case, you should get a Perl runtime error.
If you are copying code fragments, then please note that $result is a local variable and it disappears after a subroutine ends.
Do you really need to use Perl?
If not:
find /myfolder -name "A000??.txt" | xargs grep -n "umxwtdn8vtnt_n"
Will find the pattern in your files and tell you at which line...
Would you like to know if the pattern is in one or more of your files? Then:
my $not_found = 1;
for (my $count = 10; $count<= 99; $count++) {
my $result = `grep "umxwtdn8vtnt_n" /myfolder/A000$count.txt`;
if ($result) {
print $result;
$not_found = 0; # error level 0 = no error = found
last;
}
}
exit $not_found; # error level 1 = error = not found
Still trying to understand your need... what about:
my $result;
for (my $count = 10; $count<= 99; $count++) {
# you should test that A000$count.txt actually exists here
my $match = `grep "umxwtdn8vtnt_n" /myfolder/A000$count.txt`;
if ($match == "umxwtdn8vtnt_n") {
print "found $match in A000${count}.txt";
$result = $match;
last; # exit for loop
}
}
if ($result) {
# do something with it?
}
I am trying to grab the list of the files jenkins has updated from last build and latest build and stored in a perl array.
Now i have list of files and folders in source code which are considered as sensitive in terms of changes like XXXX\yyy/., XXX/TTTT/FFF.txt,...in FILE.TXT
i want that script should tell me if any these sensitive files was part of my changed files and if yes list its name so that we can double check with development team about is change before we trigger build .
How should i achieve this , and how to ,compare multiple files under one path form the changed path files .
have written below script ---which is called inside the jenkins with %workspace# as argument
This is not giving any matching result.
use warnings;
use Array::Utils qw(:all);
$url = `curl -s "http://localhost:8080/job/Rev-number/lastStableBuild/" | findstr "started by"`;
$url =~ /([0-9]+)/;
system("cd $ARGV[1]");
#difffiles = `svn diff -r $1:HEAD --summarize`;
chomp #difffiles;
foreach $f (#difffiles) {
$f = substr( $f, 8 );
$f = "$f\n";
}
open FILE, '/path/to/file'
or die "Can't open file: $!\n";
#array = <FILE>;
#isect = intersect( #difffiles, #array );
print #isect;
I have manged to solve this issue using below perl script -
sub Verifysensitivefileschanges()
{
$count1=0;
#isect = intersect(#difffiles,#sensitive);
#print "ISECT=#isect\n";
foreach $t (#isect)
{
if (#isect) {print "Matching element found -- $t\n"; $count1=1;}
}
return $count1;
}
sub Verifysensitivedirschanges()
{
$count2=0;
foreach $g (#difffiles)
{
$dirs = dirname($g);
$filename = basename($g);
#print "$dirs\n";
foreach $j (#array)
{
if( "$j" =~ /\Q$dirs/)
{print "Sensitive path files changed under path $j and file name is $filename\n";$count2=1;}
}
}
return $count2;
}
I started teaching myself Perl, and with the help of some Googling, I was able to throw together a script that would print out the file extensions in a given directory. The code works well, however, it will sometimes complain the following:
Use of uninitialized value $exts[xx] in string eq at get_file_exts.plx
I tried to correct this by initializing my array as follows: my #exts = (); but this did not work as expected.
#!/usr/bin/perl
use strict;
use warnings;
use File::Find;
#Check for correct number of arguments
if(#ARGV != 1) {
print "ERROR: Incorrect syntax...\n";
print "Usage: perl get_file_exts.plx <Directory>\n";
exit 0;
}
#Search through directory
find({ wanted => \&process_file, no_chdir => 1 }, #ARGV);
my #exts;
sub process_file {
if (-f $_) {
#print "File: $_\n";
#Get extension
my ($ext) = $_ =~ /(\.[^.]+)$/;
#Add first extension
if(scalar #exts == 0) {
push(#exts, $ext);
}
#Loop through array
foreach my $index (0..$#exts) {
#Check for match
if($exts[$index] eq $ext) {
last;
}
if($index == $#exts) {
push(#exts, $ext);
}
}
} else {
#print "Searching $_\n";
}
}
#Sort array
#exts = sort(#exts);
#Print contents
print ("#exts", "\n");
You need to test if you found an extension.
Also, you should not be indexing your array. You also do not need to manage 'push' just do it. It is not the Perl way. Your for loop should start like this:
sub process_file {
if (-f $_) {
#print "File: $_\n";
#Get extension
my ($ext) = $_ =~ /(\.[^.]+)$/;
# If we found an extension, and we have not seen it before, add it to #exts
if ($ext) {
#Loop through array to see if this is a new extension
my $newExt = 1;
for my $seenExt (#exts) {
#Check for match
if ($seenExt eq $ext) {
$newExt = 0
last;
}
}
if ($newExt) {
push #exts,$ext;
}
}
}
}
But what you really want to do is to use a hash table to record if you saw an extension
# Move this before find(...); if you want to initialize it or you will clobber the
# contents
my %sawExt;
sub process_file {
if (-f $_) {
#print "File: $_\n";
# Get extension
my ($ext) = $_ =~ /(\.[^.]+)$/;
# If we have an extension, mark that we've seen it
$sawExt{$ext} = 1
if $ext;
}
}
# Print the extensions we've seen in sorted order
print join(' ',sort keys %sawExt) . "\n";
Or even
sub process_file {
if (-f $_ && $_ =~ /(\.[^.]+)$/) {
$sawExt{$1} = 1;
}
}
Or
sub process_file {
$sawExt{$1} = 1
if -f && /(\.[^.]+)$/;
}
Once you start thinking in Perl this is the natural way to write it
The warning is complaining about a content of $exts[xx], not #exts itself.
Actually $ext can be undef, when the filename doesn't match to your regexp, for instance README.
Try like:
my ($ext) = $_ =~ /(\.[^.]+)$/ or return;
The main problem is that you aren't accounting for file names that don't contain a dot, so
my ($ext) = $_ =~ /(\.[^.]+)$/;
sets $ext to undef.
Despite the warning, processing continues by evaluating undef as the null string, failing to find that in #exts, and so percolating undef to the array as well.
The minimal change to get your code working is to replace
my ($ext) = $_ =~ /(\.[^.]+)$/;
with
return unless /(\.[^.]+)$/;
my $ext = $1;
But there is a couple of Perl lessons to be learned here. It used to be taught that good programs were well-commented programs. That was in the days of having to write efficient but incomprehensible code, but is no longer true. You should write code that is as clear as possible, and add comments only if you absolutely have to write something that isn't self-explanatory.
You should remember and use Perl idioms, and try to forget most C that you knew. For instance, Perl accepts the "here document" syntax, and it is common practice to use or and and as short-circuit operators. Your parameter check becomes
#ARGV or die <<END;
ERROR: Incorrect syntax...
Usage: perl get_file_exts.plx <Directory>
END
Perl allows for clear but concise programming. This is how I would have written your wanted subroutine
sub process_file {
return unless -f and /(\.[^.]+)$/;
my $ext = $1;
foreach my $index (0 .. $#exts) {
return if $exts[$index] eq $ext;
}
push #exts, $ext;
}
Use exists on $exts[xx] before accessing it.
exists is deprecated though as #chrsblck pointed out :
Be aware that calling exists on array values is deprecated and likely
to be removed in a future version of Perl.
But you should be able to check if it exists (and not 0 or "") simply with :
if($exts[index] && $exts[$index] eq $ext){
...
}
Sorry for the bad title but this is the best I could do! :D
I have a script which creates a new project every time the specified function is called.
Each project must be stored in its own folder, with the name of the project. But, if you don't specify a name, the script will just name it "new projectX", where X is a progressive number.
With time the user could rename the folders or delete some, so every time the script runs, it checks for the smallest number available (not used by another folder) and creates the relevant folder.
Now I managed to make a program which I think works as wanted, but I would like to hear from you if it's OK or there's something wrong which I'm unable to spot, given my inexperience with the language.
while ( defined( $file = readdir $projects_dir ) )
{
# check for files whose name start with "new project"
if ( $file =~ m/^new project/i )
{
push( #files, $file );
}
}
# remove letters from filenames, only the number is left
foreach $file ( #files )
{
$file =~ s/[a-z]//ig;
}
#files = sort { $a <=> $b } #files;
# find the smallest number available
my $smallest_number = 0;
foreach $file ( #files )
{
if ( $smallest_number != $file )
{
last;
}
$smallest_number += 1;
}
print "Smallest number is $smallest_number";
Here's a basic approach for this sort of problem:
sub next_available_dir {
my $n = 1;
my $d;
$n ++ while -e ($d = "new project$n");
return $d;
}
my $project_dir = next_available_dir();
mkdir $project_dir;
If you're willing to use a naming pattern that plays nicely with Perl's string auto-increment feature, you can simplify the code further, eliminating the need for $n. For example, newproject000.
I think I would use something like:
use strict;
use warnings;
sub new_project_dir
{
my($base) = #_;
opendir(my $dh, $base) || die "Failed to open directory $base for reading";
my $file;
my #numbers;
while ($file = readdir $dh)
{
$numbers[$1] = 1 if ($file =~ m/^new project(\d+)$/)
}
closedir($dh) || die "Failed to close directory $base";
my $i;
my $max = $#numbers;
for ($i = 0; $i < $max; $i++)
{
next if (defined $numbers[$i]);
# Directory did not exist when we scanned the directory
# But maybe it was created since then!
my $dir = "new project$i";
next unless mkdir "$base/$dir";
return $dir;
}
# All numbers from 0..$max were in use...so try adding new numbers...
while ($i < $max + 100)
{
my $dir = "new project$i";
$i++;
next unless mkdir "$base/$dir";
return $dir;
}
# Still failed - give in...
die "Something is amiss - all directories 0..$i in use?";
}
Test code:
my $basedir = "base";
mkdir $basedir unless -d $basedir;
for (my $j = 0; $j < 10; $j++)
{
my $dir = new_project_dir($basedir);
print "Create: $dir\n";
if ($j % 3 == 2)
{
my $k = int($j / 2);
my $o = "new project$k";
rmdir "$basedir/$o";
print "Remove: $o\n";
}
}
Try this:
#!/usr/bin/env perl
use strict;
use warnings;
# get the current list of files
# see `perldoc -f glob` for details.
my #files = glob( 'some/dir/new\\ project*' );
# set to first name, in case there are none others
my $next_file = 'new project1';
# check for others
if( #files ){
# a Schwartian transform
#files = map { $_->[0] } # get original
sort { $a->[1] <=> $b->[1] } # sort by second field which are numbers
map { [ $_, do{ ( my $n = $_ ) =~ s/\D//g; $n } ] } # create an anonymous array with original value and the second field nothing but digits
#files;
# last file name is the biggest
$next_file = $files[-1];
# add one to it
$next_file =~ s/(.*)(\d+)$/$1.($2+1)/e;
}
print "next file: $next_file\n";
Nothing wrong per se, but that's an awful lot of code to achieve a single objective (get the minimum index of directories.
A core module, couple of subs and few Schwartzian transforms will make the code more flexible:
use strict;
use warnings;
use List::Util 'min';
sub num { $_[0] =~ s|\D+||g } # 'new project4' -> '4', 'new1_project4' -> '14' (!)
sub min_index {
my ( $dir, $filter ) = #_;
$filter = qr/./ unless defined $filter; # match all if no filter specified
opendir my $dirHandle, $dir or die $!;
my $lowest_index = min # get the smallest ...
map { num($_) } # ... numerical value ...
grep { -d } # ... from all directories ...
grep { /$filter/ } # ... that match the filter ...
readdir $dirHandle; # ... from the directory contents
$lowest_index++ while grep { $lowest_index == num( $_ ) } readdir $dirhandle;
return $lowest_index;
}
# Ready to use!
my $index = min_index ( 'some/dir' , qr/^new project/ );
my $new_project_name = "new project $index";