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ru.perl
- RU.PERL ----------------------------------------------------------------------
From : Artem Chuprina 2:5020/400 06 Aug 2003 13:03:55
To : "Maxx L. Mazour"
Subject : Re: Hаписать копировщик файлов.
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Хмутро.
MLM> Подскажите оптимальный путь как это сделать.
system('cp', @ARGV);
Я, правда, не слишком внимательно читал, но сдается мне, это как раз описание
команды cp.
MLM> Write a program that copies files. The usage of the program is:
MLM> copy.pl <source> <destination>
MLM> Copies the <source> file to <destination>. If
MLM> <destination> is a directory, copies <source>
MLM> into that directory. Otherwise makes a copy of <source>
MLM> in the current directory.
MLM> You must use robust error-checking in this assignment. In particular, you
MLM> should exit the program (with an appropriate error message, and perhaps a
MLM> usage message) if:
MLM> Two command-line arguments were not given
MLM> The source file does not exist or can't be opened
MLM> The destination is a directory, and the directory can't be written into
MLM> The destination file already exists (see Extra Credit below)
MLM> The $! variable will contain the appropriate error messages for most of
MLM> these errors, so be sure to print the value of the $! variable in your die
MLM> statement. I will be testing every error scenario mentioned above so be
MLM> sure to test your program against all of these possible error scenarios
MLM> before submitting your application.
MLM> Your program must create an EXACT copy of the file it's copying. You should
MLM> definitely compare the byte count of your source and destination files. You
MLM> will loose points if your copy is not exactly the same as the original.
MLM> As always, the user interface to your application is important. Make sure
MLM> to notify the user with useful status messages of either a failure or
MLM> success in the copy operation attempted.
MLM> TIP: To make your error messages look nicer to the user (by showing them
MLM> only useful error feedback) you should use the newline ("\n") character at
MLM> the end of your "die" function print statement.
MLM> Like this:
MLM> or die "Can't open $destination for writing: $!.\n";
MLM> The purpose of using the newline ("\n") character in the die function
MLM> statement is to suppress the printout of the line number where your code
MLM> failed.
MLM> So with the newline character your error prints as:
MLM> Can't open recipes.txt for writing: Permission denied.
MLM> Instead of:
MLM> Can't open recipes.txt for writing: Permission denied at copy.pl line 215.
MLM>
MLM> File overwrite warning. If the destination file already exists, warn the
MLM> user, and ask them if they want to overwrite the file. If they do, then
MLM> overwrite it. Recursive file copy. Allow another usage so that if the "-r"
MLM> command line argument is specified, and the destination is a directory,
MLM> then the source directory and files in the source directory and any
MLM> directories and files below the source directory should be copied into the
MLM> destination directory.
MLM> copy.pl -r <source directory> <destination>
MLM> ---
MLM> [ася:10097303] Писать сюда:*gatomon(a)mail.ru*! Max /Фoрнит/
--
Artem Chuprina
RFC2822: <ran@ran.pp.ru>, FIDO: 2:5020/122.256, ICQ: 13038757
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