Beispiele und Tafelbilder 8.11.2021

20211108/string-ops-8.c

+#include <stdio.h>
+#include <string.h>
+
+int main (void)
+{
+  char *huber_anton = "Huber" + " " + "Anton";
+  printf ("%s\n", huber_anton);
+  return 0;
+}

20211108/string-ops-9.c

+#include <stdio.h>
+#include <string.h>
+
+int main (void)
+{
+  char *huber_anton = "Huber" + ("Anton" - " ");
+  printf ("%s\n", huber_anton);
+  return 0;
+}

20211108/write-program-1.c

+#include <stdio.h>
+#include <errno.h>
+#include <error.h>
+
+int main (void)
+{
+  FILE *f = fopen ("hello.c", "w");
+  if (!f)
+    error (errno, errno, "cannot open file");
+  fprintf (f, "#include <stdio.h>\n"
+              "\n"
+              "int main (void)\n"
+              "{\n"
+              "  printf ("Hello, world!\n");\n"
+              "  return 0;\n"
+              "}\n");
+  if (errno)
+    error (errno, errno, "cannot write to file");
+  fclose (f);
+  if (errno)
+    error (errno, errno, "cannot close file");
+  return 0;
+}

20211108/write-program-2.c

+#include <stdio.h>
+#include <errno.h>
+#include <error.h>
+
+int main (void)
+{
+  FILE *f = fopen ("hello.c", "w");
+  if (!f)
+    error (errno, errno, "cannot open file");
+  fprintf (f, "#include <stdio.h>\n"
+              "\n"
+              "int main (void)\n"
+              "{\n"
+              "  printf (\"Hello, world!\n\");\n"
+              "  return 0;\n"
+              "}\n");
+  if (errno)
+    error (errno, errno, "cannot write to file");
+  fclose (f);
+  if (errno)
+    error (errno, errno, "cannot close file");
+  return 0;
+}

20211108/write-program-3.c

+#include <stdio.h>
+#include <errno.h>
+#include <error.h>
+
+int main (void)
+{
+  FILE *f = fopen ("hello.c", "w");
+  if (!f)
+    error (errno, errno, "cannot open file");
+  fprintf (f, "#include <stdio.h>\n"
+              "\n"
+              "int main (void)\n"
+              "{\n"
+              "  printf (\"Hello, world!\\n\");\n"
+              "  return 0;\n"
+              "}\n");
+  if (errno)
+    error (errno, errno, "cannot write to file");
+  fclose (f);
+  if (errno)
+    error (errno, errno, "cannot close file");
+  return 0;
+}

20211108/write-program-4.c

+#include <stdio.h>
+#include <errno.h>
+#include <error.h>
+#include <stdlib.h>
+
+int main (void)
+{
+  FILE *f = fopen ("hello.c", "w");
+  if (!f)
+    error (errno, errno, "cannot open file");
+  fprintf (f, "#include <stdio.h>\n"
+              "\n"
+              "int main (void)\n"
+              "{\n"
+              "  printf (\"Hello, world!\\n\");\n"
+              "  return 0;\n"
+              "}\n");
+  if (errno)
+    error (errno, errno, "cannot write to file");
+  fclose (f);
+  if (errno)
+    error (errno, errno, "cannot close file");
+  system ("gcc -Wall -O hello.c -o hello");
+  system ("./hello");
+  return 0;
+}