3 files changed, 376 insertions, 0 deletions
diff --git a/1088/CH21/EX21.4/Example4.sce b/1088/CH21/EX21.4/Example4.sce
new file mode 100755
index 000000000..73a3a2f5f
--- /dev/null
+++ b/1088/CH21/EX21.4/Example4.sce
@@ -0,0 +1,150 @@
+clear
+flag=1
+mode(-1)
+clc
+
+printf("Example 4    :               Show the method of using exec command to make many streams \n")
+disp("****************************************************************")
+disp("Answer    :   ")
+
+disp("INSTRUCTIONS   : ")
+printf("\n1. Here all instructions are preloaded in the form of a demo\n\nInitially the whole perl script is displaying and then \n the result of the same can be seen in the command line interpreter.\n\n2. PLEASE MAKE SURE THAT THE PERLSCRIPT INTERPRETER\nEXISTS IN THE SYSTEM\nOR THE COMMAND WOULD NOT WORK \n\n3. PRESS ENTER AFTER EACH COMMAND to see its RESULT\n\n5. PRESS ENTER AFTER EACH RESULT TO GO TO THE NEXT COMMAND\n")
+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)='2233|a.k.shukla             |g.m.        |sales           |12/12/52|6000'
+i=i+1;f(i)='9876|jai sharma             |director  |production |12/03/50|7000'
+i=i+1;f(i)='5678|sumit chakrobarty|d.g.m      |marketing  |19/04/43|6000'
+i=i+1;f(i)='2356|barun sengupta      |director  |personnel  |11/05/47|7800'
+i=i+1;f(i)='5423|n.k. gupta              |chairman |admin       |30/08/56|5400'
+i=i+1;f(i)='1006|chanchal singhvi   |director  |sales          |03/09/38|6700'
+i=i+1;f(i)='6213|karuna ganguly      |g.m.        |accounts   |05/06/62|6300'
+i=i+1;f(i)='1265|s.n. dasgupta         |manager  |sales          |12/09/63|5600'
+i=i+1;f(i)='4290|jayant Choudhary  |executive |production|07/09/50|6000'
+i=i+1;f(i)='2476|anil aggarwal        |manager   |sales          |01/05/59|5000'
+i=i+1;f(i)='6521|lalit chowdury       |director    |marketing |26/09/45|8200'
+i=i+1;f(i)='3212|shyam saksena      |d.g.m        |accounts   |12/12/55|6000'
+i=i+1;f(i)='3564|sudhir Agarwal     |executive  |personnel  |06/07/47|7500'
+i=i+1;f(i)='2345|j.b. saxena            |g.m.           |marketing |12/03/45|8000'
+i=i+1;f(i)='0110|v.k. agrawal         |g.m.           |marketing  |31/02/40|9000'
+n=i
+printf("\n\n$ cat emp.lst      # to open the file emp.lst")
+halt(' ')
+u=mopen('emp.lst','wt')
+for i=1:n
+    mfprintf(u,"%s\n",f(i))
+    printf("%s\n",f(i))
+end
+mclose(u)
+halt('')
+clc
+i=0
+i=i+1;f(i)='#!/bin/sh'
+i=i+1;f(i)='# Script: countpat.sh -- Uses exec to handle multiple files'
+i=i+1;f(i)='#'
+i=i+1;f(i)='exec > $2                # Open file 1 for storing selected lines'
+i=i+1;f(i)='exec 3> $3               # Open file 3 for storing patterns not found'
+i=i+1;f(i)='exec 4> $4               # Open file 4 for storing invalid patterns'
+i=i+1;f(i)=''
+i=i+1;f(i)='[ $# -ne 4 ] && { echo '+ascii(34)+'4 arguments required'+ascii(34)+' ; exit 2 ; }'
+i=i+1;f(i)=''
+i=i+1;f(i)='exec < $1                 # Redirecting output'
+i=i+1;f(i)='while read pattern ; do '
+i=i+1;f(i)='      case '+ascii(34)+'$pattern'+ascii(34)+' in'
+i=i+1;f(i)='             ????) grep $pattern emp.lst ||'
+i=i+1;f(i)='                   echo $pattern not found in file 1>&3 ;;'
+i=i+1;f(i)='                *) echo $pattern not a four-character string 1>&4 ;;'
+i=i+1;f(i)='      esac'
+i=i+1;f(i)='done'
+i=i+1;f(i)='exec > \/dev/tty        # Redirects standard output back to terminal'
+i=i+1;f(i)='echo Job Over'
+n=i
+
+printf("\n# Enter the name of the shellscript file whichever you desire  \n\n")
+nam=input('$ cat  ','s')
+halt(' ')
+
+for i=1:n
+    printf("%s\n",f(i))
+end
+halt(' ')
+clc
+i=0
+i=i+1;f(i)='@echo off'
+i=i+1;f(i)='for %%x in (%*) do set /a ccc+=1'
+i=i+1;f(i)='if %ccc% neq 4 echo 4 arguments required&&goto endd'
+i=i+1;f(i)='echo.'
+i=i+1;f(i)='echo -----------Creating file %1-----------------'
+i=i+1;f(i)='set chice=y'
+
+i=i+1;f(i)=':loop1'
+i=i+1;f(i)='if /I '+ascii(34)+'%chice%'+ascii(34)+'=='+ascii(34)+'n'+ascii(34)+' goto endloop1'
+i=i+1;f(i)='set /P inp=Enter the employee-id : '
+i=i+1;f(i)='echo %inp%>>%1'
+i=i+1;f(i)='if exist len del len'
+i=i+1;f(i)='echo.%inp%>len'
+i=i+1;f(i)='for /F '+ascii(34)+'usebackq'+ascii(34)+' %%i in ('+ascii(39)+'len'+ascii(39)+') do set len=%%~zi'
+i=i+1;f(i)='del len&&set /a len-=2'
+i=i+1;f(i)='if %len% neq 4 echo %inp% is not a four-character string>>%4&&goto chi'
+i=i+1;f(i)='if exist res del res'
+i=i+1;f(i)='findstr /B '+ascii(34)+'%inp%'+ascii(34)+' emp.lst>res'
+i=i+1;f(i)='for /F '+ascii(34)+'usebackq'+ascii(34)+' %%i in ('+ascii(39)+'res'+ascii(39)+') do set siz=%%~zi'
+i=i+1;f(i)='if %siz% equ 0 echo %inp% not found in file>>%3&&goto chi'
+i=i+1;f(i)='type res>>%2'
+i=i+1;f(i)=':chi'
+i=i+1;f(i)='set /P chice=Do you want to continue?(y/n) : '
+i=i+1;f(i)='cls&&goto loop1'
+i=i+1;f(i)=':endloop1'
+i=i+1;f(i)='set /P c1=Do you want to see the file %1?(y/n) : '
+i=i+1;f(i)='if /I '+ascii(34)+'%c1%'+ascii(34)+'=='+ascii(34)+'n'+ascii(34)+' goto endloop2'
+i=i+1;f(i)='type %1'
+i=i+1;f(i)=':endloop2'
+i=i+1;f(i)='set /P c2=Do you want to see the file %2?(y/n) : '
+i=i+1;f(i)='if /I '+ascii(34)+'%c2%'+ascii(34)+'=='+ascii(34)+'n'+ascii(34)+' goto endloop3'
+i=i+1;f(i)='type %2'
+i=i+1;f(i)=':endloop3'
+i=i+1;f(i)='set /P c3=Do you want to see the file %3?(y/n) : '
+i=i+1;f(i)='if /I '+ascii(34)+'%c3%'+ascii(34)+'=='+ascii(34)+'n'+ascii(34)+' goto endloop4'
+i=i+1;f(i)='type %3'
+i=i+1;f(i)=':endloop4'
+i=i+1;f(i)='set /P c4=Do you want to see the file %4?(y/n) : '
+i=i+1;f(i)='if /I '+ascii(34)+'%c4%'+ascii(34)+'=='+ascii(34)+'n'+ascii(34)+' goto endloop2'
+i=i+1;f(i)='type %4'
+i=i+1;f(i)=':endloop5'
+i=i+1;f(i)='pause>NUL&&del %1&&del %2&&del %3&&del %4&&del res'
+n=i
+
+
+if getos()=='Linux' then
+    printf("\n\nPlease Switch to windows and then execute using the instructions\n\nThank You \n\n")
+    halt(' ')
+    exit
+end
+
+v=mopen(nam+'.sh.bat','wt')
+for i=1:n
+    mfprintf(v,"%s\n",f(i))
+end
+mclose(v)
+
+
+printf("\n# type the following command in the command line interpreter as soon as it appears")
+printf(" \n       %c  %s.sh     %c [COMMANDLINE ARGUMENTS][ENTER]\n\n",ascii(34),nam,ascii(34))
+
+printf("\n$ %s.sh  [COMMANDLINE ARGUMENTS]             #to execute the perlscript",nam)
+
+halt(' ')
+dos('start')
+printf("\n\n\n")
+halt('   ---------------->Executing ShellScript in Command Line Prompt<-------------- ')
+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)
+
+mdelete(nam+'.sh.bat')
+mdelete('emp.lst')
diff --git a/1088/CH21/EX21.4/Result4.pdf b/1088/CH21/EX21.4/Result4.pdf
new file mode 100755
index 000000000..b304ea625
--- /dev/null
+++ b/1088/CH21/EX21.4/Result4.pdf
@@ -0,0 +1,113 @@
+ ans  =
+ 
+    1.  
+ 
+-->exec('Example4.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                    :                                                                            21   
+ 
+ Chapter Title                         :                                Advanced Shell Programming   
++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+Example 4    :               Show the method of using exec command to make many streams 
+ 
+ ****************************************************************   
+ 
+ Answer    :      
+ 
+ INSTRUCTIONS   :    
+
+1. Here all instructions are preloaded in the form of a demo
+
+Initially the whole perl script is displaying and then 
+ the result of the same can be seen in the command line interpreter.
+
+2. PLEASE MAKE SURE THAT THE PERLSCRIPT INTERPRETER
+EXISTS IN THE SYSTEM
+OR THE COMMAND WOULD NOT WORK 
+
+3. PRESS ENTER AFTER EACH COMMAND to see its RESULT
+
+5. PRESS ENTER AFTER EACH RESULT TO GO TO THE NEXT COMMAND
+.............Press [ENTER] to continue.....	UNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)
+
+
+
+
+$ cat emp.lst      # to open the file emp.lst 2233|a.k.shukla             |g.m.        |sales           |12/12/52|6000
+9876|jai sharma             |director  |production |12/03/50|7000
+5678|sumit chakrobarty|d.g.m      |marketing  |19/04/43|6000
+2356|barun sengupta      |director  |personnel  |11/05/47|7800
+5423|n.k. gupta              |chairman |admin       |30/08/56|5400
+1006|chanchal singhvi   |director  |sales          |03/09/38|6700
+6213|karuna ganguly      |g.m.        |accounts   |05/06/62|6300
+1265|s.n. dasgupta         |manager  |sales          |12/09/63|5600
+4290|jayant Choudhary  |executive |production|07/09/50|6000
+2476|anil aggarwal        |manager   |sales          |01/05/59|5000
+6521|lalit chowdury       |director    |marketing |26/09/45|8200
+3212|shyam saksena      |d.g.m        |accounts   |12/12/55|6000
+3564|sudhir Agarwal     |executive  |personnel  |06/07/47|7500
+2345|j.b. saxena            |g.m.           |marketing |12/03/45|8000
+0110|v.k. agrawal         |g.m.           |marketing  |31/02/40|9000
+
+# Enter the name of the shellscript file whichever you desire  
+
+ #!/bin/sh
+# Script: countpat.sh -- Uses exec to handle multiple files
+#
+exec > $2                # Open file 1 for storing selected lines
+exec 3> $3               # Open file 3 for storing patterns not found
+exec 4> $4               # Open file 4 for storing invalid patterns
+
+[ $# -ne 4 ] && { echo "4 arguments required" ; exit 2 ; }
+
+exec < $1                 # Redirecting output
+while read pattern ; do 
+      case "$pattern" in
+             ????) grep $pattern emp.lst ||
+                   echo $pattern not found in file 1>&3 ;;
+                *) echo $pattern not a four-character string 1>&4 ;;
+      esac
+done
+exec > \/dev/tty        # Redirects standard output back to terminal
+echo Job Over
+ 
+# type the following command in the command line interpreter as soon as it appears 
+       "  h.sh     " [COMMANDLINE ARGUMENTS][ENTER]
+
+
+$ h.sh  [COMMANDLINE ARGUMENTS]             #to execute the perlscript 
+
+
+   ---------------->Executing ShellScript in Command Line Prompt<-------------- 
+
+
+$ 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)
diff --git a/1088/CH21/EX21.4/Result4.txt b/1088/CH21/EX21.4/Result4.txt
new file mode 100755
index 000000000..b304ea625
--- /dev/null
+++ b/1088/CH21/EX21.4/Result4.txt
@@ -0,0 +1,113 @@
+ ans  =
+ 
+    1.  
+ 
+-->exec('Example4.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                    :                                                                            21   
+ 
+ Chapter Title                         :                                Advanced Shell Programming   
++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+Example 4    :               Show the method of using exec command to make many streams 
+ 
+ ****************************************************************   
+ 
+ Answer    :      
+ 
+ INSTRUCTIONS   :    
+
+1. Here all instructions are preloaded in the form of a demo
+
+Initially the whole perl script is displaying and then 
+ the result of the same can be seen in the command line interpreter.
+
+2. PLEASE MAKE SURE THAT THE PERLSCRIPT INTERPRETER
+EXISTS IN THE SYSTEM
+OR THE COMMAND WOULD NOT WORK 
+
+3. PRESS ENTER AFTER EACH COMMAND to see its RESULT
+
+5. PRESS ENTER AFTER EACH RESULT TO GO TO THE NEXT COMMAND
+.............Press [ENTER] to continue.....	UNIX SHELL SIMULATOR(DEMO VERSION WITH PRELOADED COMMANDS)
+
+
+
+
+$ cat emp.lst      # to open the file emp.lst 2233|a.k.shukla             |g.m.        |sales           |12/12/52|6000
+9876|jai sharma             |director  |production |12/03/50|7000
+5678|sumit chakrobarty|d.g.m      |marketing  |19/04/43|6000
+2356|barun sengupta      |director  |personnel  |11/05/47|7800
+5423|n.k. gupta              |chairman |admin       |30/08/56|5400
+1006|chanchal singhvi   |director  |sales          |03/09/38|6700
+6213|karuna ganguly      |g.m.        |accounts   |05/06/62|6300
+1265|s.n. dasgupta         |manager  |sales          |12/09/63|5600
+4290|jayant Choudhary  |executive |production|07/09/50|6000
+2476|anil aggarwal        |manager   |sales          |01/05/59|5000
+6521|lalit chowdury       |director    |marketing |26/09/45|8200
+3212|shyam saksena      |d.g.m        |accounts   |12/12/55|6000
+3564|sudhir Agarwal     |executive  |personnel  |06/07/47|7500
+2345|j.b. saxena            |g.m.           |marketing |12/03/45|8000
+0110|v.k. agrawal         |g.m.           |marketing  |31/02/40|9000
+
+# Enter the name of the shellscript file whichever you desire  
+
+ #!/bin/sh
+# Script: countpat.sh -- Uses exec to handle multiple files
+#
+exec > $2                # Open file 1 for storing selected lines
+exec 3> $3               # Open file 3 for storing patterns not found
+exec 4> $4               # Open file 4 for storing invalid patterns
+
+[ $# -ne 4 ] && { echo "4 arguments required" ; exit 2 ; }
+
+exec < $1                 # Redirecting output
+while read pattern ; do 
+      case "$pattern" in
+             ????) grep $pattern emp.lst ||
+                   echo $pattern not found in file 1>&3 ;;
+                *) echo $pattern not a four-character string 1>&4 ;;
+      esac
+done
+exec > \/dev/tty        # Redirects standard output back to terminal
+echo Job Over
+ 
+# type the following command in the command line interpreter as soon as it appears 
+       "  h.sh     " [COMMANDLINE ARGUMENTS][ENTER]
+
+
+$ h.sh  [COMMANDLINE ARGUMENTS]             #to execute the perlscript 
+
+
+   ---------------->Executing ShellScript in Command Line Prompt<-------------- 
+
+
+$ 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)