Problem 12 (msh) Bookmark this page Changing Directories Can the effect that the command cd has in bash be accomplished in our mini-shell, msh, by forking and making the system call chdir(new_directory_path) in the child process? In order to find out, write a program called newdir which makes this system call, and call it from msh6. Yes! No! Submit Exiting msh You have used 0 of 1 attempt A proposal to the problem of exiting the shell is to have keyboard control codes (such as ctrl-C) not kill the shell by making the (parent) shell ignore those signals. If just this is done, these control codes do not terminate the shell. How, in this situation, can we exit the shell? Does the following plan provide a solution to this problem? In this case we can exit the shell by sending the shell command exit to the child process for execution. In order to find out, experiment with msh6. This plan will work. Save This plan will not work.
Problem 12 (msh) Bookmark this page Changing Directories Can the effect that the command cd has in bash be accomplished in our mini-shell, msh, by forking and making the system call chdir(new_directory_path) in the child process? In order to find out, write a program called newdir which makes this system call, and call it from msh6. Yes! No! Submit Exiting msh You have used 0 of 1 attempt A proposal to the problem of exiting the shell is to have keyboard control codes (such as ctrl-C) not kill the shell by making the (parent) shell ignore those signals. If just this is done, these control codes do not terminate the shell. How, in this situation, can we exit the shell? Does the following plan provide a solution to this problem? In this case we can exit the shell by sending the shell command exit to the child process for execution. In order to find out, experiment with msh6. This plan will work. Save This plan will not work.
Database System Concepts
7th Edition
ISBN:9780078022159
Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Chapter1: Introduction
Section: Chapter Questions
Problem 1PE
Related questions
Topic Video
Question
This is keeping Linux and
#### Changing Directories
Can the effect that the command `cd` has in `bash` be accomplished in our mini-shell, `msh`, by forking and making the system call `chdir(new_directory_path)` in the child process? In order to find out, write a program called newdir.c which makes this system call, and call it from msh6.
- [ ] Yes!
- [ ] No!
Save button is present.
---
#### Exiting msh
A proposal to the problem of exiting the shell is to have keyboard control codes (such as `ctrl-c`) not kill the shell by making the (parent) shell ignore those signals. If just this is done, these control codes do not terminate the shell. How, in this situation, can we exit the shell?
Does the following plan provide a solution to this problem?
> In this case we can exit the shell by sending the shell command `exit` to the child process for execution. In order to find out, experiment with msh6.
- [ ] This plan will work.
- [ ] This plan will not work.
---
### Problem 11 (Merlin, Batman, and Madmax)
[Bookmark this page](#)
#### What's in that file?
Assume that `file1` exists and is empty. Consider what happens when the program `arrow` is run.
```c
/* arrow.c */
int main(void) {
close(1);
open("file1",1);
printf("Merlin versus "); fflush(stdout);
close(1);
if (fork() > 0)
execlp("./batman", "./batman", (char*)0);
else
execlp("./madman", "./madman", (char*)0);
return 42;
}
```
Here are the two programs called by `arrow`:
```c
/* batman.c */
int main(void) {
open("file1",02001);
printf("Batman "); fflush(stdout);
return 24;
}
```
```c
/* madman.c */
int main(void) {
open("file1",02001);
printf("Madmax "); fflush(stdout);
return 24;
}
```
After the program runs, what does the command `echo $?` produce?
[Text box for answer]
Character for](/v2/_next/image?url=https%3A%2F%2Fcontent.bartleby.com%2Fqna-images%2Fquestion%2Fd84c1829-b5be-42b1-ba72-3bae7a546286%2F64102996-4cf6-4916-99c9-fb15f6c5f40a%2Fte64fjp_processed.png&w=3840&q=75)
Transcribed Image Text:```markdown
### Problem 12 (msh)
[Bookmark this page](#)
#### Changing Directories
Can the effect that the command `cd` has in `bash` be accomplished in our mini-shell, `msh`, by forking and making the system call `chdir(new_directory_path)` in the child process? In order to find out, write a program called newdir.c which makes this system call, and call it from msh6.
- [ ] Yes!
- [ ] No!
Save button is present.
---
#### Exiting msh
A proposal to the problem of exiting the shell is to have keyboard control codes (such as `ctrl-c`) not kill the shell by making the (parent) shell ignore those signals. If just this is done, these control codes do not terminate the shell. How, in this situation, can we exit the shell?
Does the following plan provide a solution to this problem?
> In this case we can exit the shell by sending the shell command `exit` to the child process for execution. In order to find out, experiment with msh6.
- [ ] This plan will work.
- [ ] This plan will not work.
---
### Problem 11 (Merlin, Batman, and Madmax)
[Bookmark this page](#)
#### What's in that file?
Assume that `file1` exists and is empty. Consider what happens when the program `arrow` is run.
```c
/* arrow.c */
int main(void) {
close(1);
open("file1",1);
printf("Merlin versus "); fflush(stdout);
close(1);
if (fork() > 0)
execlp("./batman", "./batman", (char*)0);
else
execlp("./madman", "./madman", (char*)0);
return 42;
}
```
Here are the two programs called by `arrow`:
```c
/* batman.c */
int main(void) {
open("file1",02001);
printf("Batman "); fflush(stdout);
return 24;
}
```
```c
/* madman.c */
int main(void) {
open("file1",02001);
printf("Madmax "); fflush(stdout);
return 24;
}
```
After the program runs, what does the command `echo $?` produce?
[Text box for answer]
Character for
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