Can any one Explain me plz the concept of Growing Array Of Structs. i mean dynamic Arrays. thanks for your Time.
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What exactly do you need help with? – Karl Knechtel Dec 13 '10 at 18:00
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14You need to make sure it gets plenty of sunlight and water it regularly – Falmarri Dec 13 '10 at 18:01
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I'm sure wiki explains it much better than someone here would care to. Why don't you read it and ask here a specific question? – ruslik Dec 13 '10 at 18:02
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Lookup Dynamic Array (like vector, ArrayList) on Wikipedia. That should get you started. – Sonny Saluja Dec 13 '10 at 18:06
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Start with a small array of some size, then whenever you need to increase the size, use realloc to do so; it is common to double the size of the array whenever you resize it.
For example:
int length = 5;
my_struct *array = NULL;
/* Initialization */
array = (my_struct *)malloc(length * sizeof(my_struct));
/* Use array[0] .. array[length - 1] */
/* When you reach the limit, resize the array */
length *= 2;
array = (my_struct *)realloc(array, length * sizeof(my_struct));
casablanca
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+1 for complete answer, but is that realloc() portable? I mean, I tried that too, but sometimes I get an error and sometimes it works. Same conditions, same system, same data. – BlackBear Dec 13 '10 at 18:25
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@BlackBear: Yes, it's very much portable. What kind of error did you get? – casablanca Dec 13 '10 at 18:30
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@BlackBear: if you didn't allocate memory for your structs' members, then you really should have any resources left out when you free that pointer. – haylem Dec 14 '10 at 00:27
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In this code, if `realloc` can't allocate enough memory, you have a memory leak. I think take into a temporary variable and check it before assigning to `array`. – Navaneeth K N Dec 14 '10 at 04:29
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Do you mean dynamic size of an array? In that case you must allocate memory fitting for you needs. See realloc
Mikkel Lund
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I have a dynamically growing string buffer implementation. You can get it from here. It uses the same malloc and realloc technique.
Navaneeth K N
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