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I've been working as a programmer for over 20 years. I started my experience when the first computer arrived at my house; an x86 (286 actually) without protect

I've been working as a programmer for over 20 years. I started my experience when the first computer arrived at my house; an x86 (286 actually) without protected memory meaning I had to code in text files and then open the IDE and compile there or command line compile within DOS. It sucked having to switch in and out of an IDE. But it taught me persistence and the ability to keep going to solve the problem. I would work late into the night before responsibilities forced me to go home to attend to first a girlfriend, then wife, then little ones. Life is about choices. You can only control your choices and nothing and no one else. What is your goal? Your desires? Your fears? If you honestly ask yourself these questions and struggle with the answer, when it comes to you it will be a wonderful moment in your life. If coding comes naturally and you enjoy it and you feed your brain sufficiently good quality food (ok a little junk food) you should be able to sustain multiple sessions of coding in one 16 hour period - but take breaks. You also should look at your sleep habits. With less than 8 hours personally I see and feel the slowdown. My brain is unable to process at full speed. You should limit coffee for when absolutely necessary. Over time your response will reduce and you will be an absolute zombie when off the coffee - not to mention the headaches, etc. So give it a try and see how your brain performs.

souprock 7y ago
The 286 did have protected memory. Each memory access was associated with a segment register, one of CS DS ES SS. The low 2 bits were for 4 permission levels, and the next bit up indicated which of two tables the MMU should use, the LDT or GDT. The high 13 bits were an index into that table, which contained 8-byte structs called descriptors. Each descriptor had a 24-bit base and a 16-bit limit. The base would remap memory. The limit would cause an access denial for out-of-range addresses. There were also permission bits, including no-execute. That MMU was used by Xenix, Windows 2, OS/2 1, RMX, and various DOS extenders. Some of those weren't very serious about controlling permissions or remapping memory, but the hardware could do it. Despite your forgetfulness, you seem like you might qualify for a job at my place. Hacking up doskey is excellent. Here, take a look: https://news.ycombinator.com/item?id=20328264 https://news.ycombinator.com/item?id=20328264

souprock 7y ago

The 286 did have protected memory. Each memory access was associated with a segment register, one of CS DS ES SS. The low 2 bits were for 4 permission levels, and the next bit up indicated which of two tables the MMU should use, the LDT or GDT. The high 13 bits were an index into that table, which contained 8-byte structs called descriptors. Each descriptor had a 24-bit base and a 16-bit limit. The base would remap memory. The limit would cause an access denial for out-of-range addresses. There were also permission bits, including no-execute. That MMU was used by Xenix, Windows 2, OS/2 1, RMX, and various DOS extenders. Some of those weren't very serious about controlling permissions or remapping memory, but the hardware could do it. Despite your forgetfulness, you seem like you might qualify for a job at my place. Hacking up doskey is excellent. Here, take a look: https://news.ycombinator.com/item?id=20328264 https://news.ycombinator.com/item?id=20328264