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#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
int Open (const char* Name, int Flags)
{
int fd;
printf ("Opening %s: ", Name);
fd = open (Name, Flags);
printf ("%d\n", fd);
return fd;
}
void Write (int fd, const void* Buf, unsigned Size)
{
int Res;
Res = write (fd, Buf, Size);
printf ("Writing %u bytes to %d: %d\n", Size, fd, Res);
}
int Read (int fd, void* Buf, unsigned Size)
{
int Res;
Res = read (fd, Buf, Size);
printf ("Reading %u bytes from %d: %d\n", Size, fd, Res);
return Res > 0? Res : 0;
}
void Close (int fd)
{
printf ("Closing %d: %d\n", fd, close (fd));
}
int main (void)
{
int fd1, fd2;
int Res;
static const char text1[] = "This goes into file #1\n";
static const char text2[] = "This goes into file #2\n";
static const char text3[] = "This goes into file #3\n";
static const char text4[] = "This goes into file #4\n";
static char Buf[200];
fd1 = Open ("foobar1", O_WRONLY|O_CREAT|O_TRUNC);
fd2 = Open ("foobar2", O_WRONLY|O_CREAT|O_TRUNC);
Write (fd1, text1, sizeof (text1) - 1);
Write (fd2, text2, sizeof (text2) - 1);
Write (fd1, text1, sizeof (text1) - 1);
Write (fd2, text2, sizeof (text2) - 1);
Close (fd1);
Close (fd2);
fd1 = Open ("foobar3", O_WRONLY|O_CREAT|O_TRUNC);
fd2 = Open ("foobar4", O_WRONLY|O_CREAT|O_TRUNC);
Write (fd1, text3, sizeof (text3) - 1);
Write (fd2, text4, sizeof (text4) - 1);
Write (fd1, text3, sizeof (text3) - 1);
Write (fd2, text4, sizeof (text4) - 1);
Close (fd1);
Close (fd2);
fd1 = Open ("foobar1", O_RDONLY);
Res = Read (fd1, Buf, sizeof (Buf));
printf ("%.*s", Res, Buf);
Res = Read (fd1, Buf, sizeof (Buf));
Close (fd1);
return 0;
}
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