initial commit / add all books

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diff --git a/1088/CH24/EX24.2/Example2.sce b/1088/CH24/EX24.2/Example2.sce
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+++ b/1088/CH24/EX24.2/Example2.sce
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+clear
+flag=1
+mode(-1)
+clc
+
+printf("Example 2    :               Show the method of showing PID,PPID in both parent and child process \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: fork.c -- A simple fork Shows PID,PPID in both parent and child*/'
+i=i+1;f(i)=''
+i=i+1;f(i)='#include <stdio.h>'
+i=i+1;f(i)='#include <sys/types.h>'
+i=i+1;f(i)=''
+i=i+1;f(i)='int main(void) {'
+i=i+1;f(i)='    pid_t pid;'
+i=i+1;f(i)='    '
+i=i+1;f(i)='    printf('+ascii(34)+'Before forking\n'+ascii(34)+');'
+i=i+1;f(i)='    pid = fork();        /* Replicates current processes */'
+i=i+1;f(i)='    '
+i=i+1;f(i)='    if(pid >0) {         /* In the parent process; make sure */'
+i=i+1;f(i)='    sleep(1);            /* That the parent does not die before child */'
+i=i+1;f(i)='    printf('+ascii(34)+'PARENT -- PID: %d PPID %d, CHILD PID: %d\n'+ascii(34)+',getpid(),getppid(),pid);}'
+i=i+1;f(i)='    '
+i=i+1;f(i)='    else if (pid == 0)    /* In the child process */'
+i=i+1;f(i)='         printf('+ascii(34)+'CHILD -- PID: %d PPID: %d\n'+ascii(34)+',getpid(),getppid());'
+i=i+1;f(i)='    else {                 /* pid must be -1 here */'
+i=i+1;f(i)='         printf('+ascii(34)+'Fork error\n'+ascii(34)+');'
+i=i+1;f(i)='         exit(1);}'
+i=i+1;f(i)='    printf('+ascii(34)+'Both process continue from here\n'+ascii(34)+');  /* In both processes */'
+i=i+1;f(i)='    exit(0);'
+i=i+1;f(i)='}'
+n=i    
+
+printf("\n\n$ cat fork.c      # to open the file emp.lst")
+halt(' ')
+u=mopen('fork.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 fork.c")
+ halt(' ')
+ printf("$ a.out")
+ halt(' ')
+ printf("Before forking\nCHILD -- PID: 1556 PPID: 1555\nBoth processes continue from here         # This statement runs in child\nPARENT -- PID: 1555 PPID: 1450,CHILD PID: 1556\nBoth processes continue from here          ...as well as in parent\n")
+ 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)
+
+