1 files changed, 50 insertions, 0 deletions
diff --git a/semestr-5/so/lista1/so21_lista_1/fileref.c b/semestr-5/so/lista1/so21_lista_1/fileref.c
new file mode 100644
index 0000000..b5d6f9f
--- /dev/null
+++ b/semestr-5/so/lista1/so21_lista_1/fileref.c
@@ -0,0 +1,50 @@
+#include "csapp.h"
+
+static char buf[256];
+
+#define LINE1 49
+#define LINE2 33
+#define LINE3 78
+
+static void do_read(int fd) {
+  /* TODO: Spawn a child. Read from the file descriptor in both parent and
+   * child. Check how file cursor value has changed in both processes. */
+  int pid = fork();
+  pid = getpid();
+  int offset = lseek(fd, 0, SEEK_CUR);
+  printf("[%d] Offset: %d\n", pid, offset);
+
+  int aux = read(fd, buf, LINE1);
+  offset = lseek(fd, 0, SEEK_CUR);
+  printf("[%d] Offset: %d\n", pid, offset);
+
+  aux = read(fd, buf, LINE2);
+  offset = lseek(fd, 0, SEEK_CUR);
+  printf("[%d] Offset: %d\n", pid, offset);
+
+  aux = read(fd, buf, LINE3);
+  offset = lseek(fd, 0, SEEK_CUR);
+  printf("[%d] Offset: %d\n", pid, offset);
+  printf("%d\n", aux);
+  exit(0);
+}
+
+static void do_close(int fd) {
+  /* TODO: In the child close file descriptor, in the parent wait for child to
+   * die and check if the file descriptor is still accessible. */
+
+  exit(0);
+}
+
+int main(int argc, char **argv) {
+  if (argc != 2)
+    app_error("Usage: %s [read|close]", argv[0]);
+
+  int fd = Open("test.txt", O_RDONLY, 0);
+
+  if (!strcmp(argv[1], "read"))
+    do_read(fd);
+  if (!strcmp(argv[1], "close"))
+    do_close(fd);
+  app_error("Unknown variant '%s'", argv[1]);
+}