How to convert an address stored in char array to actual address?

Question

I have following char array:

char hex[16] = "0x7fffa410c240"

How can i convert it into numerical address that can be assigned to another variable. Important is that i have to keep the base of value remaining the same i.e. 16 (hexadecimal). Thanks in advance.

score 6 · Answer 1 · edited Jun 20 '20 at 09:12

6

Try the function strtoull which returns unsigned long long.

On Visual Studio strtoull is not available, but _strtoui64 can probably be used.

EDIT

As R.. mentions in the comments you should probably use sscanf(hex, "%p", ..) or strtoumax which has the same prototype as strtoull but returns an uintmax_t.

edited Jun 20 '20 at 09:12

Community

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answered Sep 22 '11 at 12:13

cnicutar

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`unsigned long long` is not the same as `uint64_t` though it's at least as wide. – Jonathan Grynspan Sep 22 '11 at 12:14
Sorry, I must have edited in between, so I changed that to unsigned long long. – Sep 22 '11 at 12:16
@Vlad Lazarenko No problem. I see you also changed the link. – cnicutar Sep 22 '11 at 12:17
`long long` is not necessarily large enough to hold pointers. Either use `strtoumax` or `sscanf` with the right format for a void pointer (`%p`) or `uintmax_t` (`%ju`). – R.. GitHub STOP HELPING ICE Sep 22 '11 at 14:17
@R.. Good call, I hadn't noticed "convert an **address**". – cnicutar Sep 22 '11 at 14:27

score 1 · Accepted Answer · answered Sep 22 '11 at 14:10

1

void *ptr;
sscanf(hex, "%p", &ptr);

answered Sep 22 '11 at 14:10

R.. GitHub STOP HELPING ICE

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Thanks R, but it give following error with the use of void: "error: `void*' is not a pointer-to-object type" – BSalunke Sep 23 '11 at 04:48

How to convert an address stored in char array to actual address?

2 Answers2

EDIT