All filehandles are capable of read/write access, so you can read from and update any file or device associated with a filehandle.
However, when you associate a filehandle, you can specify the mode in which the filehandle is opened.
You can test certain features very quickly within Perl using a series of test operators known collectively as -X tests.
When using modules that are not installed in the standard directories of Perl, we need to change @INC so perl will be able to find them.
In this case too you "install" the module in a private directory, e.g.
For all the different methods used for reading information from filehandles, the main function for writing information back is the print function.Three basic file handles are - STDIN, STDOUT, and STDERR, which represent standard input, standard output and standard error devices respectively.