Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- Log

  SSH Security and You - /bin/false is *not* security

Backstory While at RIT around 2004 or 2005, I discovered that a few important machines at the datacenter allowed all students, faculty, and staff to authenticate against them via ssh. Everyone's shells appear to be set to /bin/false (or some derivative) on said machines, so the only thing you'll see after you authenticate is the login banner and your connection will close. I thought to myself, "Fine, no shell for me. I wonder if port forwarding works?" ...

   Linux,Security,/bin/false,SSH     2012-02-06 07:46:29

  Understanding lvalues and rvalues in C and C++

The terms lvalue and rvalue are not something one runs into often in C/C++ programming, but when one does, it’s usually not immediately clear what they mean. The most common place to run into these terms are in compiler error & warning messages. For example, compiling the following with gcc: int foo() {return 2;} int main() { foo() = 2; return 0; } You get: test.c: In function 'main': test.c:8:5: error: lvalue required as left operand of assignment True, this code ...

   lvalue,rvalue,C++,locator value,elaboration     2011-12-15 07:51:38

  Unix directory hierarchy history

As a beginner user of Unix or Linux, people would frequently get confused about the use of different directories of the system.  For example, there is a /bin directory under root(/), it is used to store binary files. However, there are /usr/bin and /usr/local/bin under /usr which are used for storing binary files as well. Some systems even have /opt/bin. What are the differences among them? Though there are articles explaining different directories in *nix such as Filesystem Hierarchy Stan...

   UNIX,LINUX,FILESSYTEM,DIRECTORY HIERARCHY,HISTORY     2016-10-21 23:47:17

  When to use STDERR instead of STDOUT

Every process is initialized with three open file descriptors, stdin, stdout, and stderr. stdin is an abstraction for accepting input (from the keyboard or from pipes) and stdout is an abstraction for giving output (to a file, to a pipe, to a console). That's a very simplified explanation but true nonetheless. Those three file descriptors are collectively called 'The Standard Streams'. Where does stderr come from? It's fairly straightforward to understand why stdin and stdout exist, however ...

   UNIX,STDERR,STDOUT,Difference     2012-01-14 12:07:43

  proftpd FTP Server setup on Ubuntu

A- The GUI way (for beginners only)For those who are new to linux and don't want to use a FTP server without GUI, or just for those who don't use often their FTP server and wish to set it quickly without a high level of security, there is a GTK GUI for proftpd.Be careful, it's less secure than configuring yourself your server.1- Install proftpd and gproftpd with synaptic or with this command :Code:sudo apt-get install proftpd gproftpd2-Play with the GUI and set up quickly your server.Beware...

   FTP Server,proftpd,Ubuntu,Setup     2011-04-27 11:23:10

  Format JSON data on Ubuntu

JSON now becomes a very popular data format because of its simplicity and light-weight. Nowadays many RESTful APIs will offer a choice of exchanging JSON data between the server and client. Sometimes the data may not be formatted and it cannot be easily read by human beings. It's frequently desired that the unformatted JSON data should be formatted before read. Today we will show a few ways to format JSON data on Ubuntu. Assume we have a json file test.json with below content. { "title": "Test"...

   RUBY,PYTHON,NODEJS,JSON,JQ,PERL,LINUX,UBUNTU,YAJL     2016-08-17 11:05:09

  Should All Web Traffic Be Encrypted?

The prevalence of free, open WiFi has made it rather easy for a WiFi eavesdropper to steal your identity cookie for the websites you visit while you're connected to that WiFi access point. This is something I talked about in Breaking the Web's Cookie Jar. It's difficult to fix without making major changes to the web's infrastructure. In the year since I wrote that, a number of major websites have "solved" the WiFi eavesdropping problem by either making encrypted HTTPS web traffic an accou...

   Web traffic,Security,HTTPS.Encryption,Wifi     2012-02-24 05:02:58

  Work with MySQL character set and collation

For non-English websites, they often have to deal with character set and collation if they want to store data to and read data from databases with other languages. Character set tells the database which kind of character encoding scheme to use to store or read data, collation can be simply understood as a subset of character set, it tells the database how to sort data. We talk about working with character set and collation of MySQL today.  In MySQL, if we want to store Chinese, Japanese or ...

   MySQL,character set,collation,Chinese,question mark     2012-06-17 07:07:28

  HeartBleed: Inside the heart, what happens to a normal WEB user?

To be brief, our email, IM, facebook etc. are at the risk, so try to minimize the access in these few days. Especially we should try to avoid log into our internet-banking, because we may expose our user id and password. Also later when the service providers fix the bug, we would better to change a new password for all the web accounts that are important to us. Here comes the technical explanation. You might notice before that a lot of websites use URL starting with "https". For example, https:/...

   HeartBleed,Analysis     2014-04-09 22:41:43

  What is blocking and how would you troubleshoot it?

Blocking is a common occurrence in an SQL server context, but if you are new to the world of database management you might not know what this issue entails and perhaps even fear that it is a sign of serious underlying problems. To allay your fears and clear up the mystery, here is a brief overview of blocking and the steps you can take to tackle it. Image Source: Pixabay SQL blocking explained SQL blocking according to SentryOne is an offshoot of the way that concurrent databases operate. Becau...

   SQL,DEADLOCK     2020-09-17 08:50:55

RECENT