perl 文件/路径 读写删

example8:套路模板：

8.1 读文件:

open ($fdr,"<$file")

#it is so cool, all lines can been read directly in array without while
@lineall=<$fdr>;

8.2 读文件: 

while （<fdr>）  $line=$_;

8.3 读路径

local *DH;

opendir(DH,$item)

foreach (readdir(DH))

一次性将路径读入数组

my @subdir1=readdir ($dir);

读路径下的文件:
my $subdir="/bld/xyz/toolgeneric/328";
@files=glob("$subdir/*/*");

example3: remove folder and file which is data time before one year

#!/opt/exp/bin/perl -wuse File::Path;my $subdir="/home/coolclf/rje/apaloads";@files=glob("$subdir/*");foreach my $file (@files) {        my $mtime = (stat $file)[9];        my @t = localtime $mtime;       $date = sprintf "%02u/%02u/%02u %02u:%02u:%02u", $t[4] + 1, $t[3], $t[5] % 100, $t[2], $t[1], $t[0]; ####get file time status       print $date, "\n";         my $a = ($t[5] % 100);        if ($a<13) {        #       unlink $file;             #only remove file                print "line15:$file \n";        #       system("rm -rf $file");        #method 1 :remove folder#               rmtree("$file");             #methold 2:remove folder                unlink <$file/*>;            #method 3:remove folder                rmdir $file;        }}

example4:remove.pl 有数字比较和unless 和rm folder和时间

 #!/opt/exp/bin/perl -wuse File::Path;my $subdir="/opt/cool2b";my @files=glob("$subdir/*");foreach my $file (@files) {#print "file=$file\n";@array=stat("$file");my $mtime = (stat $file)[9];my @t = localtime $mtime;my $year = ($t[5] % 100);# print ("line13:year=$year;$t[5]\n");# if ( $year eq "9" || $year eq "10" || $year eq "11" || ) {if ( $year > 8 && $year < 10 ) {print "line15:file=$file\n";rmdir $file;}#$date = sprintf "%02u/%02u/%02u %02u:%02u:%02u", $t[4] + 1, $t[3], $t[5] % 100, $t[2], $t[1], $t[0];# print $date, "\n";$uid=$array[4];# my $name="";$name=(getpwuid $uid)[0];# ($name, $passwd, $uid, $gid, $quota,# $comment, $gcos, $dir, $shell) = getpwuid($uid);#if ( defined ($name) ) {unless ( defined ($name) ) {# print ("file=$file;uid=$uid;name=$name\n");# print ("line25:file=$file\n");# rmdir $file;}# if ($name ne "" ) {# if ( $name ) {# print ("file=$file;uid=$uid;name=$name\n");# }}

example1: read from command line

钻石操作符<>是perl的读取文件每一行的操作符,是一个整行输入操作符的特例

#!/opt/exp/bin/perl -wsub say {        print @_,"\n";}my $file =$ARGV[0];open (my $fh, '<',$file) or die $!;#@a=<$fh> read file to array; then while read array one by onewhile (my $line=<$fh>) {        if ($line =~ /^bjmcl0(\d\d)/) {                if ($1>=33 and $1<=63) {                       #read from $_                       $line=~s/^/#/;                }        }        # print $line."\n";        say $line;}

example2: read and write files

#!/opt/exp/bin/perlprint "\nOpen a text file.\n";open IN, "<data1.txt";  #read a text filemy @raw=<IN>;           #using @raw store datachomp(@raw);            #skip enter keysclose(IN);#print "@raw \n";my @ref;                #make 2d array                        #'$#' = length of @rawfor ($i = 0 ; $i <= $#raw ; $i++) {    my @tmp = split(/\s/, $raw[$i]);       $ref[$i]=\@tmp; #each line is a refence in @ref        print "$i;$ref[$i];$tmp[$i] \n";           }

#!/opt/exp/bin/perl -wopen my $fh , '<' ,'1';open my $fd , ">>" ,"2";while (my $line=<$fh>) {print $fd $line;}close ($fh);close ($fd);

下面这段网络的思路我觉得挺对的：留下来仅供参考

做工程就应该是这样，熟练于一种，应用后组合

"我只知道一种操作符，> , 而且每次都只会这么写

open(my $fh, '>', 'filename') or die $!;

实在搞不清楚那么多的读写符号。我在读写文件时，现在只用 File::Slurp 模块的
read_file write_file 函数接口。

在处理文件时，我很少把输出文件和输入文件设置成一个。因为一旦搞错，数据就毁了。

通常是，设置两个不同的文件，一个读，一个写，经过确认没有问题后，也不敢把原先的文件覆写。而是备份起来。

遍历文件中，对于忽略的行，通常用 next 那么在新文件中就不出现了"

===================================

#!/opt/exp/bin/perl -wopen my $fh, '<', '1-2.txt' or die $!;while ($line=<$fh>) {        if ($line=~/felixzh1/) {                #       $line=~s/.*//g;                next;        }        print $fh1 $line;}close $fh

example 6: 遍历subdirectory files

grep /bld/xyz/toolgeneric/328/*/*

<pre code_snippet_id="637883" snippet_file_name="blog_20150407_5_4549377" name="code" class="html">ARGV表示命令行参数

#!/opt/exp/bin/perl -wmy $dir=$ARGV[0];print "$dir \n";my $fd;#my @subdir1=readdir ($dir);#print @subdir1;my $subdir="/bld/xyz/toolgeneric/328";@files=glob("$subdir/*/*");----------------------globe define files#print "line10 @files \n";

foreach my $file(@files) {        print "line12:$file \n";        my $fh;        open ($fh ,$file) or next;        while (<$fh>) {                if (/xyz/) {                        print "xyz line17 $file:,$_";                }        }        close($fh);}

</pre><pre code_snippet_id="637883" snippet_file_name="blog_20150407_5_4549377" name="code" class="html">example7:

special variables----INPLACE_EDIT

<p>$^I   内置控制编辑器的值--------------------------仅用于读写同一文件#!/usr/bin/perl -wuse strict;$^I = '.bak';while (<ARGV>) {    s/felixzh1//g;print;}</p>

example 9  find2 查找路径--递归

#!/opt/exp/bin/perl -w

use strict;
use warnings;

sub lsr {
    sub lsr;
    my $cwd = shift;

    local *DH;
    if (!opendir(DH, $cwd)) {
        warn "Cannot opendir $cwd: $! $^E";
        return undef;
    }
    foreach (readdir(DH)) {
        if ($_ eq '.' || $_ eq '..') {
            next;
        }
        my $file = $cwd.'/'.$_;
        if (!-l $file && -d _) {
            $file .= '/';
            lsr($file);
        }
       # process($file, $cwd);
        process($file);
    }
    closedir(DH);
}

my ($size, $dircnt, $filecnt) = (0, 0, 0);

sub process($$) {
    my $file = shift;
    print $file, "\n";
    if (substr($file, length($file)-1, 1) eq '/') {
        $dircnt++;
    }
    else {
        $filecnt++;
        $size += -s $file;
    }
}

lsr('.');
print "$filecnt files, $dircnt directory. $size bytes.\n";

example 10: find  非递归

use strict;use warnings;sub lsr_s {    my $cwd = shift;    my @dirs = ($cwd.'/');    my ($dir, $file);    while ($dir = pop(@dirs)) {        local *DH;        if (!opendir(DH, $dir)) {            warn "Cannot opendir $dir: $! $^E";            next;        }        foreach (readdir(DH)) {            if ($_ eq '.' || $_ eq '..') {                next;            }            $file = $dir.$_;                     if (!-l $file && -d _) {                $file .= '/';                push(@dirs, $file);            }           # process($file, $dir);            process($file);        }        closedir(DH);    }}my ($size, $dircnt, $filecnt) = (0, 0, 0);sub process($$) {    my $file = shift;    print $file, "\n";    if (substr($file, length($file)-1, 1) eq '/') {        $dircnt++;    }    else {        $filecnt++;        $size += -s $file;    }}lsr_s('.');print "$filecnt file