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With
HTML 4, centering the contents within a
div is simple. You
just use <div align="center">. E.g., if I wanted to
center the image and text below on a webpage, I could use the following
code:
<div align="center"> <img src="186px-Antinous_Mandragone_profil.jpg" alt="Antinous Mangragone profile"><br> <a href="https://commons.wikimedia.org/wiki/File:Antinous_Mandragone_profil.jpg"> Antinous Mandragone</a> </div>
The image would then be displayed in browsers as seen below:
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A user reported that she was unable to check her email today; she had also
reported the problem yesterday. When I checked
Sendmail,
which would handle her outgoing email, by using
Telnet to
connect to the well-known port for
Simple Mail Transfer Protocol (SMTP) on the server with
telnet mail.example.com 25, I saw the Sendmail banner as expected,
so I presumed her problem was likely with
Dovecot, the software on the system that would allow her to receive her
incoming email. I tried connecting to port 110, the well-known port
for Post Office Protocol version 3 (POP3) connections using
Telnet. When I saw the "Connected to" and "Escape character is" messages, I
entered the POP3 user command followed by the user's name,
but I would shortly thereafter see a "Connection closed" message every
time I tried the connection with Telnet. I never saw the "Dovecot ready" prompt
appear.
# telnet 127.0.0.1 110 Trying 127.0.0.1... Connected to 127.0.0.1. Escape character is '^]'. user nell Connection closed by foreign host. You have new mail in /var/spool/mail/root #
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To install a new package/module under
WinPython, double-click on WinPython Command Prompt in
the directory where you installed WinPython to open a command prompt window.
At the command prompt window type pip install pkgname
where pkgname is the name of the package you wish to install. If the
package is already present, you will see the message "requirement already
satisfied."
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If you need to determine whether a system on the network is an Apple system, there are a number of means you can use to help identify whether the system is, or is at least likely to be, manufactured by Apple. E.g., if the system is on the same local area network (LAN) as a system from which you can ping it, you can check the media access control (MAC) address associated with the IP address you just pinged using the Address Resolution Protocol (ARP), since the first 6 hexadecimal digits of the MAC address can be used to identify the manufacturer of the network interface controller (NIC) in the device pinged. This technique won't work if there is an intervening router between the device from which the ping is sent and the receiving device, though, since the arp address you will see when there are intervening network hops is the one of the first hop device. You can see the number of hops between the source and destination hosts using the traceroute command (tracert is the equivalent command on Microsoft Windows systems). E.g., in the example below, I issued a ping command from a Terminal window on my MacBook Pro laptop running OS X El Capitan (10.11.6). When I then peformed a reverse DNS lookup on the IP address using nslookup, the fully qualified domain name (FQDN) identified the device as an iPad. The FQDN usually won't identify the type of device so clearly, but a check of the MAC address may indicate the device was manufacturered by Apple. You can get the MAC address using the arp command.
$ ping -c 1 192.168.196.212 PING 192.168.196.212 (192.168.196.212): 56 data bytes 64 bytes from 192.168.196.212: icmp_seq=0 ttl=64 time=45.140 ms --- 192.168.196.212 ping statistics --- 1 packets transmitted, 1 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 45.140/45.140/45.140/0.000 ms $ nslookup 192.168.196.212 Server: 192.168.10.134 Address: 192.168.10.134#53 212.196.168.192.in-addr.arpa name = Margarets-iPad.abc.example.com $ arp Margarets-iPad.abc.example.com margarets-ipad.abc.example.com (192.168.196.212) at 78:7b:8a:55:bb:35 on en0 ifscope [ethernet] $
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I have an
SQLite database that I use to track approval of tasks. Every Monday,
I need to generate a count of the number of tasks approved from the prior
Tuesday through the Monday on which I'm creating the report. The approval
dates are stored in the database as an integer and I enter them in the
form 2018-05-14. I use the following
SQL command in a
Python script to determine the number I've approved
in the last week:
sql = 'SELECT COUNT(*) FROM Tasks WHERE Approved >= date(CURRENT_DATE,"-6 day")'
But I noticed that the count didn't always include the tasks I approved on the prior Tuesday. E.g., when I ran the script tonight, May 14, the number reported was 5, yet I expected the result to be 7.
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If you wish to run Python on a Microsoft Windows system, you can use WinPython. The first window you will see when run run the downloaded installation file is one for the license agreement, which notes "WinPython components are distributed as they were received from their copyright holder, under their own copyright and/or license, and without any linking with each other." WinPython itself uses the MIT license. Once you accede to the license, you will be prompted for a destination folder. By default that will be a WinPython directory created beneath the directory where you're running the downloaded file from, but you can change the location. When the installation has been completed, a window will appear where you can click on a Finish button to exit from the installation program.
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If you wish, you can add undo and redo icons to the Quick Access Toolbar at the top of the Explorer window by clicking on the icon of a downward pointing arrowhead with a horizontal line above it that appears at the top of the Explorer window. You can then select "Undo" and "Redo" from the menu that appears. Select both, so that you see checkmarks next to each of those options. You should then see curved Undo and Redo arrows next to the button you clicked on for the Customize Quick Access Toolbar. You can now use those arrows, in addition to the shortcut keys, if you prefer to undo and redo actions in the File Explorer.
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If you want to perform a "bare metal" backup of a Microsoft Windows 10 system
to an external USB
drive without a third-party application, you can use the
Backup and Restore utility that is provided by Microsoft with the
operating system. You can run the program from a command-line interface
(CLI) by
opening a command prompt window with
administrator privileges and issuing the command wbadmin start
backup -backupTarget:x -allcritical -quiet where x
is the drive letter for the drive where you wish to store the backup.
When you add the -quiet option, the backup will be run with no
prompts for the user. The --allcritical option "creates a backup
that includes all critical volumes (critical volumes contain the operating
system files and components)."
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