Working with files
Perl can work well with Files. There are several functions for working with files. The 2 basic functions are open and close. In the below example, the file c:\text.txt is assigned to the filehandle DATA. The file is opened and the first line is read and stored in $line.
Important is that, when you work with files, the meaning of backslash is destroyed. You can do this with the following:
open (DATA, "c:\\text.txt"); $line = <DATA>; print &line; close (DATA);If you assign the filehandle to a array the entire file is printed.
open (DATA, "c:\\text.txt"); open (DATA, 'c:\text.txt'); open (DATA, "c:/text.txt");
open (DATA, "c:\\text.txt"); @lines = <DATA>; print @lines; close (DATA);You can also write in a file. You do this with placing a special sign in front of the file. For writting this >, for adding to a file >>
In the following example a name is requested, that is then added to a file.
In the last example a file is assigned to the variable $file. Then the file is opened for reading the lines.
print "Please, enter you're name:"; chomp ($name=<STDIN>); open (DATA, ">>c:\\text.txt") || die "Cannot open c:\\text.txt: $! \n"; print DATA "$name \n"; close (DATA); print "You're now on the black list! \n";
$file="c:\\text.txt"; open (DATA, $file) || die "Cannot open $file: $! \n"; while (<DATA>) { print "Line $. is: $_"; } close (DATA);