46 lines
905 B
C
46 lines
905 B
C
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include <assert.h>
|
|
#include <stdio.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/stat.h>
|
|
#include <string.h>
|
|
|
|
#define BLOCK_SIZE 1
|
|
|
|
int main(int argc, char *argv[])
|
|
{
|
|
int fin,
|
|
fout;
|
|
char buf[BLOCK_SIZE];
|
|
struct stat st;
|
|
|
|
assert( argc == 3 );
|
|
|
|
fin = open(argv[1],O_RDONLY);
|
|
assert( fin >= 0 );
|
|
|
|
fstat(fin, &st);
|
|
|
|
char *src = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fin, 0);
|
|
assert(src != MAP_FAILED);
|
|
|
|
fout = open(argv[2],O_CREAT|O_RDWR|O_TRUNC,0600);
|
|
assert( fout >= 0 );
|
|
|
|
ftruncate(fout, st.st_size);
|
|
|
|
char *dst = mmap(NULL, st.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fout, 0);
|
|
assert(dst != MAP_FAILED);
|
|
|
|
memcpy(dst, src, st.st_size);
|
|
|
|
munmap(src, st.st_size);
|
|
munmap(dst, st.st_size);
|
|
|
|
close(fin);
|
|
close(fout);
|
|
|
|
return 0;
|
|
|
|
} |