c - What is the purpose of array[index] = 0;? -

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char dev[20] = "dev_name"; char dest[32]; strncpy(dest,dev,sizeof(dev)); dest[sizeof(dev)-1] = 0;

what dest[sizeof(dev)-1] = 0; means?

in code, assuming size analogous sizeof, 

 dev_name[size(dec_name)-1] = 0;

dev_name[size(dec_name)-1] points last element of array, remember c arrays use 0 based indexing.

then, definition, string in c exxentially char array with null-termination, if want use char array string, must have null-termination.

0 ascii value of nul or null. so, essentially, you're putting null-terminator char array.


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