Perl - 目录


以下是用于处理目录的标准函数。

opendir DIRHANDLE, EXPR  # To open a directory
readdir DIRHANDLE        # To read a directory
rewinddir DIRHANDLE      # Positioning pointer to the begining
telldir DIRHANDLE        # Returns current position of the dir
seekdir DIRHANDLE, POS   # Pointing pointer to POS inside dir
closedir DIRHANDLE       # Closing a directory.

显示所有文件

有多种方法可以列出特定目录中的所有可用文件。首先,让我们使用简单的方法来使用glob运算符获取并列出所有文件-

#!/usr/bin/perl

# Display all the files in /tmp directory.
$dir = "/tmp/*";
my @files = glob( $dir );

foreach (@files ) {
   print $_ . "\n";
}

# Display all the C source files in /tmp directory.
$dir = "/tmp/*.c";
@files = glob( $dir );

foreach (@files ) {
   print $_ . "\n";
}

# Display all the hidden files.
$dir = "/tmp/.*";
@files = glob( $dir );
foreach (@files ) {
   print $_ . "\n";
}

# Display all the files from /tmp and /home directories.
$dir = "/tmp/* /home/*";
@files = glob( $dir );

foreach (@files ) {
   print $_ . "\n";
}

这是另一个示例,它打开一个目录并列出该目录中的所有可用文件。

#!/usr/bin/perl

opendir (DIR, '.') or die "Couldn't open directory, $!";
while ($file = readdir DIR) {
   print "$file\n";
}
closedir DIR;

打印您可能使用的 C 源文件列表的另一个示例是 -

#!/usr/bin/perl

opendir(DIR, '.') or die "Couldn't open directory, $!";
foreach (sort grep(/^.*\.c$/,readdir(DIR))) {
   print "$_\n";
}
closedir DIR;

创建新目录

您可以使用mkdir函数创建一个新目录。您需要拥有创建目录所需的权限。

#!/usr/bin/perl

$dir = "/tmp/perl";

# This creates perl directory in /tmp directory.
mkdir( $dir ) or die "Couldn't create $dir directory, $!";
print "Directory created successfully\n";

删除目录

您可以使用rmdir函数来删除目录。您需要拥有删除目录所需的权限。此外,在尝试删除该目录之前,该目录应该为空。

#!/usr/bin/perl

$dir = "/tmp/perl";

# This removes perl directory from /tmp directory.
rmdir( $dir ) or die "Couldn't remove $dir directory, $!";
print "Directory removed successfully\n";

更改目录

您可以使用chdir函数更改目录并转到新位置。您需要拥有更改目录并进入新目录所需的权限。

#!/usr/bin/perl

$dir = "/home";

# This changes perl directory  and moves you inside /home directory.
chdir( $dir ) or die "Couldn't go inside $dir directory, $!";
print "Your new location is $dir\n";