Script started on Mon Nov 17 17:29:01 2025
macbook:logs> echo attendance code 462
attendance code 462
macbook:logs> cd ../programs/unix_ch13
macbook:unix_ch13> cat talk.c
// Linux for Programmers and Users, Glass/Ables, page 503
#include <stdio.h>
#include <signal.h>
#include <stdbool.h>
#include <unistd.h>
#include <string.h>

#define READ 0 /* The index of the read end of the pipe */
#define WRITE 1 /* The index of the write end of the pipe */

char* phrase = "Stuff this in your pipe and smoke it";

int main() {
  int fd [2], bytesRead;

  char message [100]; /* Parent process' message buffer */

  pipe (fd);          /*Create an unnamed pipe */
  if (fork () == 0)   /* Child, writer */
  {
    close(fd[READ]); /* Close unused end */
    write (fd[WRITE],phrase, strlen (phrase) + 1); /* include NULL*/
    close (fd[WRITE]); /* Close used end */
  }
  else /* Parent, reader*/
  {
    close (fd[WRITE]); /* Close unused end */
    bytesRead = read (fd[READ], message, 100);
    printf ("Read %d bytes: %s\n", bytesRead, message); /* Send */
    close (fd[READ]); /* Close used end */
  }

  return 0;
}
macbook:unix_ch13> gcc talk.c -o talk
macbook:unix_ch13> ./talk
Read 37 bytes: Stuff this in your pipe and smoke it
macbook:unix_ch13> cd ../unix_ch5
macbook:unix_ch5> vi testfor.sh
macbook:unix_ch5> cp testfor.sh testfor2.sh 
macbook:unix_ch5> vi testfor2.sh 
macbook:unix_ch5> ls -l testf*
-rwxr-xr-x  1 mweeks  staff  61 Sep 12 15:21 testfor.sh
-rwxr-xr-x  1 mweeks  staff  89 Nov 17 18:03 testfor2.sh
macbook:unix_ch5> ./testfor2.sh 
param: red
param: green
param: blue
param: yellow
param: orange
macbook:unix_ch5> cat testfor2.sh 
params="red green blue yellow orange"
for value in $params
do
  echo param: $value
done

macbook:unix_ch5> cat testif.sh 
echo "enter a word: "
read v1
if [ -e $v1 ]
then
  echo "A file by that name exists."
else
  echo "No file by that name exists."
fi 
macbook:unix_ch5> ./testif.sh 
enter a word: 
testfor2.sh
A file by that name exists.
macbook:unix_ch5> ./testif.sh
enter a word: 
testforty2.sh
No file by that name exists.
macbook:unix_ch5> cat test_file_exists.sh 
if [ -e "$1" ]; then
  echo "The file exists."
fi%                                                                             macbook:unix_ch5> 
macbook:unix_ch5> ./test_file_exists.sh testfor2.sh
The file exists.
macbook:unix_ch5> ./test_file_exists.sh testforty2.sh
macbook:unix_ch5> grep until *
testuntil.sh:until [ $x -gt 3 ]
macbook:unix_ch5> cat testuntil.sh 
x=1
until [ $x -gt 3 ]
do
  echo x = $x
  x=`expr $x + 1`
done 
macbook:unix_ch5> ./testuntil.sh 
x = 1
x = 2
x = 3
macbook:unix_ch5> cd ../unix_ch12
macbook:unix_ch12> gcc reverse.c
clang: error: no such file or directory: 'reverse.c'
clang: error: no input files
macbook:unix_ch12> ls rev*
reverse_unix_ch12.c	reverse_unix_original.c
macbook:unix_ch12> gcc reverse_unix_ch12.c
macbook:unix_ch12> ./a.out
reverse ("cat") = tac
reverse ("noon") = noon
macbook:unix_ch12> cd make_project
macbook:make_project> ls *h
db.h	parts.h	supps.h
macbook:make_project> cat db.h
#include <stdio.h>
#include "parts.h"
#include "supps.h"
 
macbook:make_project> cat parts.
cat: parts.: No such file or directory
macbook:make_project> cat parts.h
#include <stdbool.h>
#include <stdio.h>

#define N 10

int a[N];

void array_set(int, int);
int array_length();
void array_init(int *);

macbook:make_project> cat supps.h
#include <stdbool.h>
#include <stdio.h>

#define N 10

bool is_prime(int);
macbook:make_project> cat supps.c
/*********************************************************
 * From C PROGRAMMING: A MODERN APPROACH, by K. N. King  *
 * Copyright (c) 1996 W. W. Norton & Company, Inc.       *
 * All rights reserved.                                  *
 * This program may be freely distributed for class use, *
 * provided that this copyright notice is retained.      *
 *********************************************************/

/* prime.c (Chapter 9, page 162) */
/* Tests whether a number is prime */

// altered a bit to use as an example for "make"

#include "supps.h"


bool is_prime(int n)
{
  int divisor;

  if (n <= 1) return false;
  for (divisor = 2; divisor * divisor <= n; divisor++)
    if (n % divisor == 0)
      return false;
  return true;
}

macbook:make_project> cat parts.c 
#include "parts.h"



void array_init(int *p) {
  int i;

  for (i=0; i<N; i++) {
    *p = 0;
    p++;
  }
}

int array_length() {
  return N;
}

void array_set(int index, int value) {
  if ((index >= 0) && (index < N))
    a[index] = value;
}

macbook:make_project> cat db.c
#include "db.h"

int main() {

  int i;

  printf("The array has %d values\n", array_length());
  array_init(a);

  i = array_length() - 2;

  array_set(i, 5);

  if (is_prime(a[i]))
    printf("Value %d is prime.\n", a[i]);
  else
    printf("Value %d is not prime.\n", a[i]);

  return 0;
}
macbook:make_project> 
macbook:make_project> ls 
db			Makefile		supps.c
db.c			parts.c			supps.h
db.h			parts.h
example_makefile	README.txt
macbook:make_project> cat Makefile
  db:   db.o supps.o parts.o 
	echo "make db" ; gcc db.o supps.o parts.o -o db

  db.o: db.c db.h supps.h parts.h 
	echo "make db.o" ; gcc -c db.c

  supps.o: supps.c supps.h
	echo "make supps.o" ; gcc -c supps.c

  parts.o: parts.c parts.h
	echo "make parts.o" ; gcc -c parts.c

macbook:make_project> make 
echo "make db.o" ; gcc -c db.c
make db.o
echo "make supps.o" ; gcc -c supps.c
make supps.o
echo "make parts.o" ; gcc -c parts.c
make parts.o
echo "make db" ; gcc db.o supps.o parts.o -o db
make db
macbook:make_project> vi Makefile 
macbook:make_project> make       
make: `db' is up to date.
macbook:make_project> touch supps.c
macbook:make_project> ls -l supps.c
-rw-r--r--  1 mweeks  staff  747 Nov 17 18:30 supps.c
macbook:make_project> make         
echo "make supps.o" ; gcc -c supps.c
make supps.o
echo "make db" ; gcc db.o supps.o parts.o -o db
make db
macbook:make_project> 
macbook:make_project> exit

Saving session...
...copying shared history...
...saving history...truncating history files...
...completed.

Script done on Mon Nov 17 18:39:57 2025