Perl Tutorial - 56: Listing Files in a Folder Video Lecture | Perl Building Blocks: An Introduction to Perl - Back-End Programming

hello guys welcome to my channel this is
the 56 to role in this course and in
this video we're gonna see how we can
count the number of files as well as see
all the files in a particular folder
using Perl so I've got a script opened
up here it's called fine underscore
files and in this script on line number
three I have created a scalar variable
called source which has you know the
path to a folder called Perl scripts
within the Documents folder on my system
and if I would browse to this Perl
scripts folder you you can see that I
have all the script files that we have
used in the tutorials in this course so
you know there are 62 files in this
folder and I am NOT just pointing to the
folder I'm actually pointing to all the
files in the folder that have the dot PL
extension so the asterisk here means
that the file name could be anything as
long as the extension is dot PL we are
interested in that file the next thing
that we are doing is we are creating an
array variable called list and I'm doing
that using the at the rate symbol here
and to it I am assigning all the file
names which have the dot P extension and
I'm doing that using the glab or the
glob function so you type glob and then
within parenthesis you pass the the
scalar variable source that we have just
created here on line number three now
that we have all the files that satisfy
this particular condition we can obtain
the number of files in the folder easily
by simply passing the scalar value of
this list to a scalar variable called
size and we could use a scalar function
for it but we don't really have to do
that even an equality operator an equal
to symbol between the scalar operator
the scalar variable and the less
variable would do the job and that's
what we're doing here on line number 6
and then on line number 8 I have a print
statement that's first going to display
the text the total number of files in
the directory and then it's going to
actually show the number of files right
so that as I said is 62 and then finally
you know if you would
just see the contents of the array
variable list then you would see full
path name right so let's say there's a
file called argument so you would see C
Drive users and then mother and then
documents and then Perl scripts and then
arguments dot pl so I've counted the
number of characters from C here till
the forward slash here and that comes
out to 38 so I do not want to see the
first 38 characters I'm just interested
in seeing the names of the files and
that's why I've got a for each loop here
on line number 10 and I'm going to eye
trait over the contents of this array
variable list and then inside the for
each loop on line number 12 I have a
print statement that's gonna use the sub
string or the sub STR function and it's
going to you know pick one file name at
a time and it's going to start
displaying 38 index onwards right and of
course after displaying each file name
it's going to print the newline
character so that we see the next file
name on a new line I'll make sure that
this file is saved when I press f5 and I
scroll to the top I first see the total
number of files in the directory is 62
and then after a gap of Lion
I see all the file names so ours
underscore number dot PL and are doing
start PL and remember if I don't use
this for each loop and if I just you
know print the contents of Atlas then as
I said we would see full path names and
you know that is obviously not very
pleasant to the eye so I hope you guys
had fun watching this video you may
subscribe to my channel if you haven't
already I'm going to see you in the next
tutorial till then take care