Question

我是Perl的新手。任何人都可以解释它在线下的含义吗？

if ( -s $errorlog ) {
    open( LOG, "$errorlog" ) or die "Unable to open logfile:$!\n";
    while (<LOG>) {
        my ($line) = $_;
        chomp($line);
        if ( $line =~ m/\d\d-\d\d \d\d:\d\d:\d\d ERROR / )

非常感谢您的回复。

Answer 1

测试文件是否为空。

if (-s $filename) {
    # The file is not empty
}

更多细节：

## if the file is not empty
if ( -s $errorlog ) {
    ## Open the file and assign the reference to variable LOG
    ## in case of failure, stop the program -- die
    ## with error message "Unable to open logfile:<FILE NAME>\n"
    open( LOG, "$errorlog" ) or die "Unable to open logfile:$!\n";

    ## While not end of file
    while (<LOG>) {
        ## read next line into local variable `line`
        my ($line) = $_;

        ## remove clutter from it (http://perldoc.perl.org/functions/chomp.html)
        chomp($line);

        ## if the line looks like "11-05 01:01:12 ERROR"
        ## Regular expression used, probably to test for a date 
        ## after which string `ERROR` follows
        if ( $line =~ m/\d\d-\d\d \d\d:\d\d:\d\d ERROR / )

Perl中的（-s $ filename）是什么意思？

1 个答案: