sizeof function

[dayananda.ms]

Hi all,

I just have basic doubt on sizeof. any function name size is giving as 1 byte.

int main()
{
printf("%d", sizeof(main); // or
printf("%d", sizeof(printf));
return 0;
}

or some user defined function also the same.

Please any one tell, why it is giving as 1 byte, if it pointer i can understand that it is 4 bytes.

[b2bwild]

#include<iostream>
using namespace std;
int main()
{
cout << sizeof(main());
return 0;
}

It returns 4.

[gerard4143]

It should be returning either 4 or 8 bytes depending on the system 32 or 64 bit....Gerard4143

[b2bwild]

he wrote sizeof(main) instead sizeof(main())

[gerard4143]

he wrote sizeof(main) instead sizeof(main())

I always thought you could use sizeof(main)...I guess I learned something today...Gerard4143

[PastAsNew]

Remember that although a function pointer can be assigned to from the function name, the function name itself is not a pointer. K&R states that sizeof cannot be applied to an operator of function type, and that if you do you will get an implementation-dependant unsigned integer ... in your case 1 it would seem.

I think the trick is to do sizeof(&main).

[Rubberman]

Remember that although a function pointer can be assigned to from the function name, the function name itself is not a pointer. K&R states that sizeof cannot be applied to an operator of function type, and that if you do you will get an implementation-dependant unsigned integer ... in your case 1 it would seem.

I think the trick is to do sizeof(&main).

When at C, listen to Captains Kernighan and Ritchie. They will keep you on course!

[dayananda.ms]

Hi All,

I have to find the executable file path by using the PID (process ID).

User will input some PID and required output is corresponding executable file path.
For this i have to write a C program using system call. Anyone help me.

[PastAsNew]

Hi All,

I have to find the executable file path by using the PID (process ID).

User will input some PID and required output is corresponding executable file path.
For this i have to write a C program using system call. Anyone help me.

I don't know the answer, but you'll stand a much better chance of the right person seeing this if you post it into its own new thread, rather than this one that's all about sizeof.

Edit: Ah I see you did. This one was obviously a mistook

[Rubberman]

Hi All,

I have to find the executable file path by using the PID (process ID).

User will input some PID and required output is corresponding executable file path.
For this i have to write a C program using system call. Anyone help me.

Open /proc/<pid>/cmdline for read, then read the single line found in the file. That is the command line that was used to start the process.