restructure

TMP/Practice/trash/lect.c

@@ -0,0 +1,24 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+
+int main(int argc, char *argv[]){
+    int fd_src, fd_dst;
+    caddr_t addr_src, addr_dst;
+    struct stat filestat;
+    fd_src = open(argv[1], O_RDONLY);
+    fd_dst = open(argv[2], O_RDWR | O_CREAT);
+    fstat(fd_src, &filestat);
+    lseek(fd_dst, filestat.st_size - 1, SEEK_SET);
+    write(fd_dst, "", 1);
+    addr_src = mmap((caddr_t)0, filestat.st_size, PROT_READ, MAP_SHARED, fd_src, 0);
+    addr_dst = mmap((caddr_t)0, filestat.st_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_dst, 0);
+    memcpy(addr_dst, addr_src, filestat.st_size);
+    exit(0);
+}