Computer Systems: A Programmer's Perspective (3rd Edition)
3rd Edition
ISBN: 9780134092669
Author: Bryant, Randal E. Bryant, David R. O'Hallaron, David R., Randal E.; O'Hallaron, Bryant/O'hallaron
Publisher: PEARSON
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Chapter 8, Problem 8.20HW
Use execve to write a
The 1s program gets the width of the screen from the COLUMNS environment variable. If COLUMNS is Unset, then 1s assumes that the screen is 80 columns wide. Thus, you can check your handling of the environment variables by setting the COLUMNS environment to something less than 80:
linux> setenv COLUMNS
linux> ./my1s
.
. //Output is 40 columns wide
.
linux> unsetenv COLUMNS
linux> ./my1s
.
//Output is now 80 columns wide
.
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Chapter 8 Solutions
Computer Systems: A Programmer's Perspective (3rd Edition)
Ch. 8.2 - Prob. 8.1PPCh. 8.4 - Prob. 8.2PPCh. 8.4 - Prob. 8.3PPCh. 8.4 - Prob. 8.4PPCh. 8.4 - Practice Problem 8.5 (solution page 797) Write a...Ch. 8.4 - Practice Problem 8.6 (solution page 797) Write a...Ch. 8.5 - Practice Problem 8.7 (solution page 798) Write a...Ch. 8.5 - Prob. 8.8PPCh. 8 - Prob. 8.9HWCh. 8 - In this chapter, we have introduced some functions...
Ch. 8 - How many hello output lines does this program...Ch. 8 - How many "hello' output lines does this program...Ch. 8 - Prob. 8.13HWCh. 8 - How many hello output lines does this program...Ch. 8 - How many "hello lines does this program print?Ch. 8 - Prob. 8.16HWCh. 8 - Prob. 8.17HWCh. 8 - Consider the following program: Determine which of...Ch. 8 - How many lines of output does the following...Ch. 8 - Use execve to write a program called my1s whose...Ch. 8 - What are the possible output sequences from the...Ch. 8 - Write your own version of the Unix system function...Ch. 8 - One of your colleagues is thinking of using...Ch. 8 - Modify the program in Figure 8.18 so that the...Ch. 8 - Write a version of the fgets function, called...
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