1 files changed, 77 insertions, 0 deletions
diff --git a/1088/CH24/EX24.13/Example13.sce b/1088/CH24/EX24.13/Example13.sce
new file mode 100755
index 000000000..c38922d79
--- /dev/null
+++ b/1088/CH24/EX24.13/Example13.sce
@@ -0,0 +1,77 @@
+clear
+flag=1
+mode(-1)
+clc
+
+printf("Example 13    :    Show the method of running two programs in a pileline \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 pipe2.c -- Runs two programs in a pipeline Child runs cat, parent runs tr */'
+i=i+1;f(i)='#include <stdio.h>'
+i=i+1;f(i)='#include <unistd.h>'
+i=i+1;f(i)=''
+i=i+1;f(i)='void quit(char *message,int exit_status);'
+i=i+1;f(i)='int main(void) { '
+i=i+1;f(i)='    int fd[2];             /* To be fille dup by pipe() */'
+i=i+1;f(i)='    '
+i=i+1;f(i)='    if (pipe(fd) < 0)      /* Now have four descriptors for pipe */'
+i=i+1;f(i)='        quit('+ascii(34)+'pipe'+ascii(34)+', 1);'
+i=i+1;f(i)='    switch (fork()) {'
+i=i+1;f(i)='           case -1: quit('+ascii(34)+'fork'+ascii(34)+', 2);'
+i=i+1;f(i)='           '
+i=i+1;f(i)='           case 0: close(fd[0]); /* CHILD - Close read end first */'
+i=i+1;f(i)='                   dup2(fd[1], STDOUT_FILENO); /* Connect stdout to write end */'
+i=i+1;f(i)='                   close(fd[1]);      /* and close original descriptor */'
+ i=i+1;f(i)='                  execlp('+ascii(34)+'cat'+ascii(34)+', '+ascii(34)+'cat'+ascii(34)+','+ascii(34)+'/etc/hosts.equiv'+ascii(34)+', (char *) 0);'
+i=i+1;f(i)='                   '
+i=i+1;f(i)='           default: close(fd[1]);     /* PARENT -- Close write end first */'
+i=i+1;f(i)='                    dup2(fd[0], STDIN_FILENO);   /* Connect stdin to read end */'
+i=i+1;f(i)='                    close(fd[0]);        /* and close original descriptor */'
+i=i+1;f(i)='                    execlp('+ascii(34)+'tr'+ascii(34)+', '+ascii(34)+'tr'+ascii(34)+', '+ascii(34)+''+ascii(39)+'[a-z]'+ascii(39)+''+ascii(34)+','+ascii(34)+''+ascii(39)+'[A-Z]'+ascii(39)+''+ascii(34)+',(char *) 0);'
+i=i+1;f(i)='                    quit('+ascii(34)+'tr'+ascii(34)+', 4);'
+i=i+1;f(i)='}'
+i=i+1;f(i)='}'
+n=i
+ 
+
+printf("\n\n$ cat pipe2.c      # to open the file emp.lst")
+halt(' ')
+u=mopen('pipe2.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("SATURN\nEARTH\nMERCURY\nJUPITER\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)
+
+