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haas:spring2015:cprog:projects:eocehints [2015/04/19 20:39] – [the neatness of binary and octal (and hex)] wedgehaas:spring2015:cprog:projects:eocehints [2015/04/19 20:44] (current) – [0x1: more octal] wedge
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 If you were to convert "640" to an integer value 640, that would be 640 in base 10; 640(10) to base 8 would be: 1200 If you were to convert "640" to an integer value 640, that would be 640 in base 10; 640(10) to base 8 would be: 1200
  
-If you pass that decimal 640 to the chmod() function, you'd end up with the sticky bit being set (T in other) along with user write, and NOTHING else. Not 640 as we desire.+If you pass that decimal 640 to the chmod() function, you'd end up with the sticky bit being set (T in other) along with user write, and NOTHING else. Not 0640 as we desire, but instead 01200.
  
 So, entering 640 on the command-line would not result in a direct conversion to octal 0640... some converting will be in order. So, entering 640 on the command-line would not result in a direct conversion to octal 0640... some converting will be in order.
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 As you can see, even if you had a 0640, the leading zero would be dropped in the conversion, because **atoi(3)** is apparently only cognizant of decimal values (and good, because that would have taken the fun out of this particular problem... you stand to learn some important things by working through this process). As you can see, even if you had a 0640, the leading zero would be dropped in the conversion, because **atoi(3)** is apparently only cognizant of decimal values (and good, because that would have taken the fun out of this particular problem... you stand to learn some important things by working through this process).
  
-And also, do you see that regardless of displaying it in octal, decimal, or hex, it is the same value? They're all being sourced from an integer variable called result... a regular old int... so it ultimately is up to how we instruct the computer to interpret it... after all, EVERYTHING is in binary, even if we are thinking through the problem exclusively in decimal.+And also, do you see that regardless of displaying it in octal, decimal, or hex, it is the same value? They're all being sourced from an integer variable called result... a regular old int... so it ultimately is up to how we instruct the computer to interpret it... after all, EVERYTHING is in binary, even if we are thinking through the problem exclusively in a different base.
  
 > Why doesn't adding the leading zero make it octal? > Why doesn't adding the leading zero make it octal?
haas/spring2015/cprog/projects/eocehints.1429475986.txt.gz · Last modified: 2015/04/19 20:39 by wedge