Null pointer
.
Now is there programmer who can escape from the clutches of the null pointer? I think no. It is like the “Yeldra natu sani” every C programmer is destined to suffer from it. The above error popped up from Windows Media player.
Meanwhile, I wonder what they teach at those so called premier institutes of computer engineering. One of computer science grad names a variable as “anded” because it stores the result of bit wise and of two other variables.
# Tcl snippet
set anded [hexpr $addr & $def(MASK)]
puts $anded
.
Small mistakes. Large consequences
During the Persian Gulf war in 1991 American Patriot missile failed to intercept an incoming Iraqi Scud missile killing 28. The cause of tragic mishap was an in accurate conversion of time, measured in tenths of seconds, to the binary values as they are stored in the computer. Specifically elapsed time was measured by the systems internal clock in tenths of a second and stored in binary numbers. Then the results need to be multiplied bu 10 to produce the time in seconds. This calculation was performed using 24 bits. Hence the value 1/10, which has non terminating binary expansion, was truncated after 24 bits, resulting in a minute error. This truncation error, when multiplied by the large number giving the time in tenths of a secon, led fatal mistake.
