my $dbh = DBI->connect("DBI:SQLite:sample.db", "", "", DBI_PERLSCRIPTIVEAUTOCOMMIT|DBI_TRX_INDEPENDENT) or die "Cannot connect to SQLite database: $DBI::errstr"; my $sql = "CREATE TABLE IF NOT EXISTS people (id
open BEDROCK, ">", $file_name; open LOG, ">>", &logfile_name(); Bad 文件句柄 关闭文件句柄 close BEDROCK; 严重错误和 die 可以和 C 中使用 perror 类似,用 die 函数: if (!open LOG, ">>logfile") { die "Cannot create logfile:$!"; } 使用文件句柄 if (!open PASSWD, "/etc/passwd"...
1．命令格式： mkdir [选项] 目录... 2．命令功能： 通过 mkdir 命令可以实现在指定位置创建以 DirNa...
GNU General Public License, which may be foundinthe Perl5source kit. Complete documentationforPerl, including FAQ lists, should be foundonthissystemusing"man perl"or"perldoc perl". If you have access to the Internet, point your browser at http://www.perl.org/, the Perl Home Page.12345678 ...
O_RDONLY Read only.O_WRONLY Write only.O_RDWR Readandwrite.O_CREAT Create the fileifit doesn.t already exist.O_EXCL Failifthe file already exists.O_APPEND Append to an existing file.O_TRUNC Truncate the file before opening.O_NONBLOCK Non-blocking mode.O_NDELAY Equivalent of O_NONBLOCK.O_...
否定真正的价值! 或not返回特殊的假值。 Perl编程语言提供以下类型的条件语句。 Sr.No.声明和说明 (The ? : Operator) 我们检查conditional operator ? : conditional operator ? :可用于替换if...else语句。 它有以下一般形式 - Exp1 ? Exp2 : Exp3; 12...
O_CREAT Create the file if it doesn.t already exist. O_EXCL Fail if the file already exists. O_APPEND Append to an existing file. O_TRUNC Truncate the file before opening. O_NONBLOCK Non-blocking mode. O_NDELAY Equivalent of O_NONBLOCK. ...
if ($output_file) { print "Output will be saved to $output_file\n"; } Ⅱ、需要实现更复杂的逻辑,比如参数的默认值、互斥选项、参数的重复等 示例: #!/usr/bin/perl use strict; use warnings; use Getopt::Long; my $input_file = “./input_file.txt”; ...
/usr/bin/perl -w# Copyright 2008 Amazon Technologies, Inc. Licensed under the Apache License, Version 2.0 (the "License");# you may not use this file except in compliance with the License. You may obtain a copy of the License at:## https://aws.amazon.com/apache2.0## This file is ...
O_CREAT Create the file if it doesn.t already exist. O_EXCL Fail if the file already exists. O_APPEND Append to an existing file. O_TRUNC Truncate the file before opening. O_NONBLOCK Non-blocking mode. O_NDELAY Equivalent of O_NONBLOCK. ...