How cast type int with atoi() to Int32

Question

I've got a piece of C code:

Int32 tmp = atoi("314");

It throws an error:

error: Int32 undeclared (first use in this function)

I have no idea why? Could you help me?

Maybe it is problem with #includes:

sys/socket.h
netinet/in.h
arpa/inet.h
stdio.h
stdlib.h
string.h
strings.h

i think you want `int tmp = atoi("314");` – thumbmunkeys Mar 21 '12 at 14:27 — thumbmunkeys, Mar 21 '12 at 14:27

score 4 · Accepted Answer · answered Mar 21 '12 at 14:30

4

There is no standard type called Int32. You're probably looking for

int tmp = atoi("314");

If you need a 32-bit integer, the standard type is int32_t defined in inttypes.h or stdint.h.

answered Mar 21 '12 at 14:30

Ken Wayne VanderLinde

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Also note that `atoi` is not useful if your goal is to ensure that the 32-bit numbers can be read (`int` could be smaller than 32 bit). In that case you'd need `strtol` or `sscanf` with the `SCNd32` macro from `inttypes.h`. – R.. GitHub STOP HELPING ICE Mar 21 '12 at 15:00

score 2 · Answer 2 · answered Mar 21 '12 at 14:44

2

There is no built-in Int32 type in C. You can include stdint.h for int32_t and uint32_t though. But in this case, you probably want to use int.

int tmp = atoi("314");

answered Mar 21 '12 at 14:44

ApprenticeHacker

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Teja · Answer 3 · 2012-03-21T14:43:41.957

-1

If you want Int32 variable you should use

<arm.h>

Check this link. http://pubs.opengroup.org/onlinepubs/009619299/apdxa.htm

edited Mar 21 '12 at 14:43

answered Mar 21 '12 at 14:27

Teja

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*Really*? Why would you want to include that random header? And also, that defines `int32`, not `Int32`. – mattjgalloway Mar 21 '12 at 14:42
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Err... shouldn't he just include `stdint.h` instead of some random possibly platform-specific header. – ApprenticeHacker Mar 21 '12 at 14:45

How cast type int with atoi() to Int32

3 Answers3