Updated the Repo

assignment-2/README.md

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+# Assignment 2
+## CS1217 Operating Systems (Spring 2023)
+---
+
+### Setting up Git on your Virtual Machines
+
+You will need a Unix environment for this (MacOS, or Linux). 
+
+Follow the sections **Generating a new SSH key** and **Adding your SSH key to the ssh-agent** from [this link](https://docs.github.com/en/authentication/connecting-to-github-with-ssh/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent), and then follow the section **Adding a new SSH key to your account** from [this link](https://docs.github.com/en/authentication/connecting-to-github-with-ssh/adding-a-new-ssh-key-to-your-github-account).
+
+Make sure that you do this with the same GitHub Account that you're using to access the assignment. 
+
+Finally, you will have to take one last step. Execute the following command on your Terminal (copy-paste this, because the placements of the apostrophes are important):
+
+```
+echo "Host github.com
+  Hostname ssh.github.com
+  Port 443" >> ~/.ssh/config
+```
+
+### Cloning this Repository
+
+1. There will be a big green button saying *Code* at the top of the page. Click that, click on *Local* and then click on *SSH*. Copy the link that is shown there (it should start with something like ```git@github.com:...```). 
+2. Open a Terminal on your VM, and run the command ```git clone [SSH URL]``` where ```[SSH URL]``` is what you copied in Step 1. 
+3. Run ```ls```, and you will be able to see the name of the directory that the repository got cloned to.
+4. Run ```cd [DIRECTORY NAME]``` where ```[DIRECTORY NAME]``` is the name of the repository directory that you saw in Step 3.
+
+Those are all the cloned files. If you're using a Desktop Version of Ubuntu, you will be able to find this cloned folder in your Home directory. Use these files during the assignment. 

assignment-2/cpu-print.c

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+#include <unistd.h>
+#include <stdio.h>
+#include <sys/time.h>
+
+int main(int argc, char *argv[]) 
+
+{
+  unsigned int i;
+  int count = 0;
+  struct timeval tv;
+
+  while(1)
+    {
+      for(i = 0; i < 1000000; i++)
+	{
+	  gettimeofday(&tv, NULL);
+	  printf("%u sec, %u usec\n", tv.tv_sec, tv.tv_usec);
+	}
+      count++;
+      printf("round %d complete\n", count);
+    }
+}

assignment-2/cpu.c

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+#include <unistd.h>
+#include <stdio.h>
+
+int main(int argc, char *argv[]) 
+
+{
+  unsigned int i,j;
+  while(1)
+    {
+      j = 1;
+      for(i = 1; i <= 10; i++)
+	{
+	  j = j*i;
+	}
+    }
+}
+
+

assignment-2/disk.c

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+#include <unistd.h>
+#include <stdio.h>
+#include<stdlib.h>
+#include <sys/types.h>
+#include <string.h>
+#include <errno.h>
+
+#define FNAME_SIZE 100
+#define MAX_FILE_NO 10000
+#define BLOCK_SIZE 1024
+
+int main(int argc, char *argv[])
+{
+
+  int n, file_no;
+  FILE *fp;
+  char dest_file_name[FNAME_SIZE];
+  char buf[BLOCK_SIZE];
+
+  while(1)
+    {
+      file_no = rand() % MAX_FILE_NO;
+
+      bzero(dest_file_name, FNAME_SIZE);
+      sprintf(dest_file_name, "files/foo%d.txt", file_no);
+
+      fp = fopen(dest_file_name, "rb");
+      if (fp == NULL) {
+	perror("Can't open dest file");
+	exit(1);
+      }
+
+      bzero(buf,BLOCK_SIZE);
+      while  ( (n = (int)fread( buf, 1, BLOCK_SIZE, fp )) > 0)
+	{
+	  //do nothing with the read data;
+	  bzero(buf,BLOCK_SIZE);
+	}
+
+       fclose(fp);
+    }
+}

assignment-2/disk1.c

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+#include <unistd.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <string.h>
+#include <errno.h>
+#include<stdlib.h>
+
+#define FNAME_SIZE 100
+#define MAX_FILE_NO 10000
+#define BLOCK_SIZE 1024
+
+int main(int argc, char *argv[])
+{
+
+  int n, file_no;
+  FILE *fp;
+  char dest_file_name[FNAME_SIZE];
+  char buf[BLOCK_SIZE];
+
+  while(1)
+    {
+      //file_no = rand() % MAX_FILE_NO;
+      file_no = 0;
+
+      bzero(dest_file_name, FNAME_SIZE);
+      sprintf(dest_file_name, "files/foo%d.txt", file_no);
+
+      fp = fopen(dest_file_name, "rb");
+      if (fp == NULL) {
+	perror("Can't open dest file");
+	exit(1);
+      }
+
+      bzero(buf,BLOCK_SIZE);
+      while  ( (n = (int)fread( buf, 1, BLOCK_SIZE, fp )) > 0)
+	{
+	  //do nothing with the read data;
+	  bzero(buf,BLOCK_SIZE);
+	}
+
+       fclose(fp);
+    }
+}

assignment-2/script.py

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+import os
+for i in range(10000):
+	file_name = f"foo{i}.txt"
+	file_size = 2*1024*1024 #size in Bytes
+	with open(file_name, "wb") as f:
+		f.write(os.urandom(file_size))

assignment-3/.cvsignore

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+*.asm
+*.d
+*.sym
+_*
+kernel
+user1
+userfs
+usertests
+xv6.img
+vectors.S
+bochsout.txt
+bootblock
+bootother
+bootother.out
+parport.out
+fmt

assignment-3/.dir-locals.el

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+((c-mode
+  (indent-tabs-mode . nil)
+  (c-file-style . "bsd")
+  (c-basic-offset . 2)))

assignment-3/.gdbinit

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+set $lastcs = -1
+
+define hook-stop
+  # There doesn't seem to be a good way to detect if we're in 16- or
+  # 32-bit mode, but in 32-bit mode we always run with CS == 8 in the
+  # kernel and CS == 35 in user space
+  if $cs == 8 || $cs == 35
+    if $lastcs != 8 && $lastcs != 35
+      set architecture i386
+    end
+    x/i $pc
+  else
+    if $lastcs == -1 || $lastcs == 8 || $lastcs == 35
+      set architecture i8086
+    end
+    # Translate the segment:offset into a physical address
+    printf "[%4x:%4x] ", $cs, $eip
+    x/i $cs*16+$eip
+  end
+  set $lastcs = $cs
+end
+
+echo + target remote localhost:26000\n
+target remote localhost:26000
+
+echo + symbol-file kernel\n
+symbol-file kernel

assignment-3/.gdbinit.tmpl

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+set $lastcs = -1
+
+define hook-stop
+  # There doesn't seem to be a good way to detect if we're in 16- or
+  # 32-bit mode, but in 32-bit mode we always run with CS == 8 in the
+  # kernel and CS == 35 in user space
+  if $cs == 8 || $cs == 35
+    if $lastcs != 8 && $lastcs != 35
+      set architecture i386
+    end
+    x/i $pc
+  else
+    if $lastcs == -1 || $lastcs == 8 || $lastcs == 35
+      set architecture i8086
+    end
+    # Translate the segment:offset into a physical address
+    printf "[%4x:%4x] ", $cs, $eip
+    x/i $cs*16+$eip
+  end
+  set $lastcs = $cs
+end
+
+echo + target remote localhost:1234\n
+target remote localhost:1234
+
+echo + symbol-file kernel\n
+symbol-file kernel

assignment-3/.gitignore

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+*.asm
+*.d
+*.sym
+_*
+##############
+# *.img
+# *.out
+# *.o
+# mkfs
+# entryother
+# initcode
+##############
+kernel
+user1
+userfs
+usertests
+xv6.img
+vectors.S
+bochsout.txt
+bootblock
+bootother
+bootother.out
+parport.out
+fmt

assignment-3/BUGS

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+formatting:
+	need to fix PAGEBREAK mechanism
+
+sh:
+	can't always runcmd in child -- breaks cd.
+	maybe should hard-code PATH=/ ?
+

assignment-3/LICENSE

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+The xv6 software is:
+
+Copyright (c) 2006-2018 Frans Kaashoek, Robert Morris, Russ Cox,
+                        Massachusetts Institute of Technology
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+