initial commit / add all books

2 files changed, 227 insertions, 0 deletions

diff --git a/1088/CH24/EX24.9/Example9.sce b/1088/CH24/EX24.9/Example9.sce
new file mode 100755
index 000000000..38effb613
--- /dev/null
+++ b/1088/CH24/EX24.9/Example9.sce
@@ -0,0 +1,118 @@
+clear
+flag=1
+mode(-1)
+clc
+
+printf("Example 9    :    Show the effect of creating a mock child shell which accepts and executes commands \n")
+disp("****************************************************************")
+disp("Answer    :   ")
+disp("INSTRUCTIONS   : ")
+halt(' ')
+disp("1.These programs are part of systems programming PURELY in Unix and the commands have NO EQUIVALENT IN SCILAB")
+halt(' ')
+disp("2.However the .c files which are displayed here are also made into a seperate file.If you are a unix user then try compiling and running the programme with gcc or cc compiler")
+halt(' ')
+disp("3.The outputs displayed here are just MOCK OUTPUTS which are DISPLAYED IN THE TEXTBOOK")
+halt(' ')
+disp("4.The inconvenience is regretted.")
+halt('.............Press [ENTER] to continue.....')
+halt("")
+clc
+printf("\tUNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)\n\n\n")
+i=0
+i=i+1;f(i)='/* Program: shell.c -- Accepts user input as a command to be executed. Users the strtok library function for parsing command line*/'
+i=i+1;f(i)='#include <stdio.h>'
+i=i+1;f(i)='#include <unistd.h>'
+i=i+1;f(i)='#include <string.h>        /*for strtok*/'
+i=i+1;f(i)='#include <wait.h>'
+i=i+1;f(i)=''
+i=i+1;f(i)='#define BUFSIZE 200         /*Maximum size for the command line */'
+i=i+1;f(i)='#define ARGVSIZE 40         /* Maximum number of arguments*/'
+i=i+1;f(i)='#define DELIM '+ascii(34)+'\n\t\r'+ascii(34)+'       /* White-space delimiters for strtok */'
+i=i+1;f(i)=''
+i=i+1;f(i)='int main(int argc, char **argv) {'
+i=i+1;f(i)='    int i,n ;'
+i=i+1;f(i)='    char buf[BUFSIZE + 1];      /* Stores the entered command line */'
+i=i+1;f(i)='    char *clargs[ARGVSIZE];     /* Stores the arguments strings */'
+i=i+1;f(i)='    int returnval ;             /* Used by wait */'
+i=i+1;f(i)='    for (;;) {                  /* Loop forever */'
+i=i+1;f(i)='         n = 1;'
+i=i+1;f(i)='         write(STDOUT_FILENO, '+ascii(34)+'Shell> '+ascii(34)+',7);  /*Display a prompt */'
+i=i+1;f(i)='         read(STDIN_FILENO, buf, BUFSIZE);    /* Read user input into buf */'
+i=i+1;f(i)='         if (!strcmp(buf, '+ascii(34)+'exit\n'+ascii(34)+'))'
+i=i+1;f(i)='         exit(0);                 /* Terminate if user enters exit */'
+i=i+1;f(i)='                                  /* Now parse buf to extract the */'
+i=i+1;f(i)='         clargs[0] = strtok(buf, DELIM); /* first word */'
+i=i+1;f(i)='                                   /* Continue parsing until ... */'
+i=i+1;f(i)='         while ((clargs[n] = strtok(NULL, DELIM) != NULL)'
+i=i+1;f(i)='         n++;                      /* ...all words are extracted */'
+i=i+1;f(i)='         '
+i=i+1;f(i)='         clargs[n] = NULL;         /* Set last arguments pointer to NULL */'
+i=i+1;f(i)='         switch(fork()) {'
+i=i+1;f(i)='                        case 0:'
+i=i+1;f(i)='                             if ((execvp(clargs[0], &clargs[0])) < 0)'
+i=i+1;f(i)='                             exit(200);    /* We will check this value later */'
+i=i+1;f(i)='                     default:       /* Int the parent */'
+i=i+1;f(i)='                     wait(&returnval); /*After the command has completed.. */' 
+i=i+1;f(i)='                     printf('+ascii(34)+'Exit status of command: %d\n'+ascii(34)+',WEXITSTATUS(returnval));'
+i=i+1;f(i)='                     for (i=0; i<=n ;i++)  /*...initialise both... */'
+i=i+1;f(i)='                     clargs[i] = '+ascii(34)+'\0'+ascii(34)+';     /*the argument array ...*/'
+i=i+1;f(i)='                     for (i=0; i<BUFSIZE+1; i++)'
+i=i+1;f(i)='                     buf[i] = '+ascii(39)+'\0'+ascii(39)+';     /* ... and the buffer that stores command */'
+i=i+1;f(i)='                     }                  /* line, so next command can work with */'
+i=i+1;f(i)='           }                            /* an initialized buffer and argument */'
+i=i+1;f(i)='}                                        /* array */'
+i=i+1;f(i)=''
+n=i           
+
+    
+
+printf("\n\n$ cat shell.c      # to open the file emp.lst")
+halt(' ')
+u=mopen('shell.c','wt')
+for i=1:n
+    mfprintf(u,"%s\n",f(i))
+    printf("%s\n",f(i))
+end
+mclose(u)
+halt('')
+clc
+
+halt(' ')
+ printf("$ cc shell.c")
+ halt(' ')
+ printf("$ a.out ")
+ halt(' ')
+ printf("Shell> ")
+ sleep(1500)
+ printf("grep  joker  /etc/passwd")
+ halt(' ')
+ printf("Exit status of command: 1                      #grep returns 1 if pattern not found")
+ halt(' ')
+ printf("Shell> ")
+ sleep(1500)
+ printf("pwd                             #Is this the shell builtin? ")
+halt(' ')
+printf("/users1/home/staff/sumit\nExit status of command: 0")
+ halt(' ')
+ printf("Shell> ")
+sleep(1500)
+printf("ls -lu  /usr/bin/pwd               # Now check the access time of on-disk pwd")
+halt(' ')
+printf("-r-xr-xr-x      1  root        bin     4360   May  29  01:33    /use/bin/pwd\nExit status of command: 0        # Disk file has just been accessed! ")
+ halt(' ')
+ printf("Shell> ")
+sleep(1500)
+printf("exit")
+halt('')
+printf("$_              # Back to parent shell") 
+halt(' ')
+
+printf("\n\n\n$ exit        #To exit the current simulation terminal and return to Scilab console\n\n")
+halt("........# (hit [ENTER] for result)")
+//clc()
+
+printf("\n\n\t\t\tBACK TO SCILAB CONSOLE...\nLoading initial environment')
+sleep(1000)
+
+
diff --git a/1088/CH24/EX24.9/Result9.txt b/1088/CH24/EX24.9/Result9.txt
new file mode 100755
index 000000000..b1eba0ff0
--- /dev/null
+++ b/1088/CH24/EX24.9/Result9.txt
@@ -0,0 +1,109 @@
+ ans  =

+ 

+    1.  

+ 

+-->exec('Example9.sci')

+ 

+-->clear

+ 

+-->flag=1

+ flag  =

+ 

+    1.  

+ 

+-->mode(-1)

+Current date is 23-Jun-2013 

+ 

+Welcome to the Textbook Companionship Project 2013 

++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

+ 

+ Book Title                             :       UNIX CONCEPTS AND APPLICATIONS    

+ 

+ Book Edition                         :                                                                           4   

+ 

+ Book Author                          :                                                    Sumitabha Das   

++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

+ 

+ Code Author                          :                                                     Pranav Bhat T   

++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

+ 

+ Chapter Number                    :                                                                            24   

+ 

+ Chapter Title                         :                              Systems programming II- Files   

++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

+Example 9    :    Show the effect of creating a mock child shell which accepts and executes commands 

+ 

+ ****************************************************************   

+ 

+ Answer    :      

+ 

+ INSTRUCTIONS   :    

+  

+ 1.These programs are part of systems programming PURELY in Unix and the commands have NO EQUIVALENT IN SCILAB   

+  

+ 2.However the .c files which are displayed here are also made into a seperate file.If you are a unix user then try compiling and 

+       running the programme with gcc or cc compiler                                                                              

+  

+ 3.The outputs displayed here are just MOCK OUTPUTS which are DISPLAYED IN THE TEXTBOOK   

+  

+ 4.The inconvenience is regretted.   

+.............Press [ENTER] to continue.....	UNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)

+

+

+

+

+$ cat shell.c      # to open the file emp.lst /* Program: shell.c -- Accepts user input as a command to be executed. Users the strtok library function for parsing command line*/

+#include <stdio.h>

+#include <unistd.h>

+#include <string.h>        /*for strtok*/

+#include <wait.h>

+

+#define BUFSIZE 200         /*Maximum size for the command line */

+#define ARGVSIZE 40         /* Maximum number of arguments*/

+#define DELIM "\n\t\r"       /* White-space delimiters for strtok */

+

+int main(int argc, char **argv) {

+    int i,n ;

+    char buf[BUFSIZE + 1];      /* Stores the entered command line */

+    char *clargs[ARGVSIZE];     /* Stores the arguments strings */

+    int returnval ;             /* Used by wait */

+    for (;;) {                  /* Loop forever */

+         n = 1;

+         write(STDOUT_FILENO, "Shell> ",7);  /*Display a prompt */

+         read(STDIN_FILENO, buf, BUFSIZE);    /* Read user input into buf */

+         if (!strcmp(buf, "exit\n"))

+         exit(0);                 /* Terminate if user enters exit */

+                                  /* Now parse buf to extract the */

+         clargs[0] = strtok(buf, DELIM); /* first word */

+                                   /* Continue parsing until ... */

+         while ((clargs[n] = strtok(NULL, DELIM) != NULL)

+         n++;                      /* ...all words are extracted */

+         

+         clargs[n] = NULL;         /* Set last arguments pointer to NULL */

+         switch(fork()) {

+                        case 0:

+                             if ((execvp(clargs[0], &clargs[0])) < 0)

+                             exit(200);    /* We will check this value later */

+                     default:       /* Int the parent */

+                     wait(&returnval); /*After the command has completed.. */

+                     printf("Exit status of command: %d\n",WEXITSTATUS(returnval));

+                     for (i=0; i<=n ;i++)  /*...initialise both... */

+                     clargs[i] = "\0";     /*the argument array ...*/

+                     for (i=0; i<BUFSIZE+1; i++)

+                     buf[i] = '\0';     /* ... and the buffer that stores command */

+                     }                  /* line, so next command can work with */

+           }                            /* an initialized buffer and argument */

+}                                        /* array */

+

+ $ cc shell.c $ a.out  Shell> grep  joker  /etc/passwd Exit status of command: 1                      #grep returns 1 if pattern not found Shell> pwd                             #Is this the shell builtin?  /users1/home/staff/sumit

+Exit status of command: 0 Shell> ls -lu  /usr/bin/pwd               # Now check the access time of on-disk pwd -r-xr-xr-x      1  root        bin     4360   May  29  01:33    /use/bin/pwd

+Exit status of command: 0        # Disk file has just been accessed!  Shell> exit$_              # Back to parent shell 

+

+

+$ exit        #To exit the current simulation terminal and return to Scilab console

+

+........# (hit [ENTER] for result)

+

+			BACK TO SCILAB CONSOLE...

+Loading initial environment 

+-->diary(0)