init commit

3sem/seminars/l10/01.c

@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <wait.h>
+
+// cmd < file1 >> file2
+
+int
+main(int argc, char **argv)
+{
+    char *file1 = argv[2];
+    char *file2 = argv[3];
+    char *cmd = argv[1];
+
+    if (!fork()) {
+        int fin = open(file1, O_RDONLY);
+        int fout = open(file2, O_WRONLY | O_APPEND | O_CREAT, 0666);
+
+        dup2(fin, 0);
+        dup2(fout, 1);
+
+        execlp(cmd, cmd, NULL);
+        _exit(1);
+    } else {
+        wait(NULL);
+    }
+
+    return 0;
+}

3sem/seminars/l10/02.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <wait.h>
+
+// cmd1 | cmd2
+
+int
+main(int argc, char **argv)
+{
+    char *cmd1 = argv[1];
+    char *cmd2 = argv[2];
+
+    int fd[2];
+    pipe(fd);
+
+    if (!fork()) {
+        dup2(fd[1], 1);
+        close(fd[0]);
+
+        execlp(cmd1, cmd1, NULL);
+        _exit(1);
+    } else if (!fork()) {
+        dup2(fd[0], 0);
+        close(fd[1]);
+
+        execlp(cmd2, cmd2, NULL);
+        _exit(1);
+    } else {
+        close(fd[0]);
+        close(fd[1]);
+    }
+
+    while (wait(NULL) != -1)
+        ;
+
+    return 0;
+}

3sem/seminars/l10/03.c

@@ -0,0 +1,63 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <wait.h>
+
+int
+main(int argc, char **argv)
+{
+    int n = strtoll(argv[1], NULL, 10);
+
+    int fd1[2];
+    int fd2[2];
+    pipe(fd1);
+    pipe(fd2);
+
+    int tmp = 1;
+    write(fd2[1], &tmp, sizeof(tmp));
+
+    if (!fork()) {
+        int i = 0;
+        close(fd1[0]);
+        close(fd2[1]);
+
+        while (i < n) {
+            read(fd2[0], &i, sizeof(i));
+            if (i > n) {
+                break;
+            }
+            printf("Channel %d: %d\n", 1, i);
+            i++;
+            write(fd1[1], &i, sizeof(i));
+        }
+
+        return 0;
+    } else if (!fork()) {
+        int i = 0;
+        close(fd2[0]);
+        close(fd1[1]);
+
+        while (i < n) {
+            read(fd1[0], &i, sizeof(i));
+            if (i > n) {
+                break;
+            }
+            printf("Channel %d: %d\n", 2, i);
+            i++;
+            write(fd2[1], &i, sizeof(i));
+        }
+
+        return 0;
+    } else {
+        close(fd1[0]);
+        close(fd1[1]);
+        close(fd2[0]);
+        close(fd2[1]);
+    }
+
+    while (wait(NULL) != -1)
+        ;
+
+    return 0;
+}