problem with mmap

[Neal Becker]

On linux, I don't understand why:

f = open ('/dev/eos', 'rw')
m = mmap.mmap(f.fil eno(), 1000000, prot=mmap.PROT_ READ|mmap.PROT_ WRITE,
flags=mmap.MAP_ SHARED)

gives 'permission denied', but this c++ code works:

#include <sys/mman.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <iostream>

int main() {
int fd = open ("/dev/eos", O_RDWR);
void* m = mmap (NULL, 1000000, PROT_READ|PROT_ WRITE, MAP_SHARED, fd, 0);
std::cout << m << '\n';
}

[Carl Banks]

On Apr 25, 9:37 am, Neal Becker <ndbeck...@gmai l.comwrote:

On linux, I don't understand why:

f = open ('/dev/eos', 'rw')
m = mmap.mmap(f.fil eno(), 1000000, prot=mmap.PROT_ READ|mmap.PROT_ WRITE,
flags=mmap.MAP_ SHARED)

gives 'permission denied',

Try

f = open('/dev/eos', 'r+')
Carl Banks

[hdante]

On Apr 25, 4:43*pm, Carl Banks <pavlovevide... @gmail.comwrote :

On Apr 25, 9:37 am, Neal Becker <ndbeck...@gmai l.comwrote:

On linux, I don't understand why:

f = open ('/dev/eos', 'rw')
m = mmap.mmap(f.fil eno(), 1000000, prot=mmap.PROT_ READ|mmap.PROT_ WRITE,
flags=mmap.MAP_ SHARED)

gives 'permission denied',

Try

f = open('/dev/eos', 'r+')

Carl Banks

The equivalent code in python should be:

import os, mmap
f = os.open('/dev/eos', os.O_RDWR)
m = mmap.mmap(f, 1000000, prot=mmap.PROT_ READ|mmap.PROT_ WRITE,
flags=mmap.MAP_ SHARED)

That should work like the C++ code.