ЭЛЕКТРОННАЯ БИБЛИОТЕКА КОАПП
Сборники Художественной, Технической, Справочной, Английской, Нормативной, Исторической, и др. литературы.



9.8. Removing a Directory and Its Contents

Problem

You want to remove a directory tree recursively without using rm -r.

Solution

Use the finddepth function from File::Find, shown in Example 9.3.

Example 9.3: rmtree1

#!/usr/bin/perl
# rmtree1 - remove whole directory trees like rm -r
use File::Find qw(finddepth);
die "usage: $0 dir ..\n" unless @ARGV;
*name = *File::Find::name;
finddepth \&zap, @ARGV;
sub zap {
    if (!-l && -d _) {
        print "rmdir $name\n";
        rmdir($name)  or warn "couldn't rmdir $name: $!";
    } else {
        print "unlink $name";
        unlink($name) or warn "couldn't unlink $name: $!";
    }
}

Or use rmtree from File::Path, as shown in Example 9.4.

Example 9.4: rmtree2

#!/usr/bin/perl
# rmtree2 - remove whole directory trees like rm -r
use File::Path;
die "usage: $0 dir ..\n" unless @ARGV;
    foreach $dir (@ARGV) {
    rmtree($dir);
}

WARNING: These programs remove an entire directory tree. Use with extreme caution!

Discussion

The File::Find module exports both a find function, which traverses a tree in the (essentially random) order the files occur in the directory, as well as a finddepth function, which is guaranteed to visit all the files underneath a directory before visiting the directory itself. This is exactly what we need to remove a directory and its contents.

We have to use two different functions, rmdir and unlink. The unlink function deletes only files, and rmdir only deletes empty directories. We need to use finddepth to make sure that we've first removed the directory's contents before we rmdir the directory itself.

Check first that the file isn't a symbolic link before determining if it's a directory. -d returns true for both a directory and a symbol link to a directory. stat, lstat, and the file test operators like -d all use the operating system call stat (2), which returns all the information kept about a file in an inode. These functions and operators retain that information and let you do more tests on the same file with the special underscore ( _ ) filehandle. This avoids redundant system calls that would return the same information, slowly.

See Also

The unlink , rmdir, lstat, and stat functions in perlfunc (1) and in Chapter 3 of Programming Perl; the documentation for the standard File::Find module; your system's rm (1) and stat (2) manpages; the -X section of perlfunc (1), and the "Named Unary and File Test Operators" section of Chapter 2 of Programming Perl


Previous: 9.7. Processing All Files in a Directory RecursivelyPerl CookbookNext: 9.9. Renaming Files
9.7. Processing All Files in a Directory RecursivelyBook Index9.9. Renaming Files