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March 20th, 2013, 08:56 AM
#1
help needed
what is the difference between unsigned char in[] and const unsigned char in[]
Thanks
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March 20th, 2013, 09:23 AM
#2
Re: help needed
const means that the data cannot be changed.
Code:
const unsigned char in[] = "qwerty";
in contains the characters "qwerty" which cannot be changed.
Code:
unsigned char in[] = "qwerty";
in again contains the characters "qwerty" but the characters in the array can be changed.
Code:
const unsigned char in[] = "qwerty";
unsigned char in2[] = "qwerty";
in[0] = 'z';
in2[0] = 'z';
In the above, the line highlighted produces a compile error as the code is trying to change the q to a z but in is defined as const so changes are not allowed. The in2 change is allowed as in2 is not defined as const.
Hopes that helps.
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C++23 Compiler: Microsoft VS2022 (17.6.5)
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