From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 1088/CH24/EX24.16/Result16.txt | 110 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 110 insertions(+)
 create mode 100755 1088/CH24/EX24.16/Result16.txt

(limited to '1088/CH24/EX24.16/Result16.txt')

diff --git a/1088/CH24/EX24.16/Result16.txt b/1088/CH24/EX24.16/Result16.txt
new file mode 100755
index 000000000..2225a189d
--- /dev/null
+++ b/1088/CH24/EX24.16/Result16.txt
@@ -0,0 +1,110 @@
+ ans  =
+ 
+    1.  
+ 
+-->exec('Example16.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 16    :       Show the method of using fork and exec to run a user-defined
+ program and kill it in 5 seconds if not completed 
+ 
+ ****************************************************************   
+ 
+ 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 killprocess.c      # to open the file emp.lst /* Program: killprocess.c -- Uses fork and exec to run a user-defined program and kills it if it doesnt complete in 5 seconds */
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <signal.h>
+
+pid_t pid;
+int main(int argc, char **argv) {
+    int i,status;
+    void death_handler(int signo);   /* A common signal handler this time */
+    
+    signal(SIGCHLD, death_handler);  /* death_handler is invoked when a */
+    signal(SIGALRM, death_handler);  /* child dies or an alarm is recieved */
+    
+    switch (pid = fork()) {
+           case -1: printf("Fork error\n");
+           case 0: execvp(argv[1],&argv[1]);   /* Execute command */
+                   perror("exec");
+                   break;
+           default: alarm(5);      /* Will send SIGALRM after 5 seconds */
+                   pause();        /* Will return when SIGCHILD signal is received */
+                   printf("Parent dies\n");
+                   }
+           exit(0);
+           }
+    
+    void death_handler(int signo) {      /* This common handler pics up the */
+          int status;                    /* exit status for normal termination */
+          signal(signo, death_handler);   /* but sends the SIGTERM signal if */
+          switch(signo) {                   /* command doesnt complete in 5 seconds */
+              case SIGCHLD: waitpid(-1, &status, 0); /* Same as wait(&status); */
+              printf("Child dies; exit status: %d\n",WEXITSTATUS(status));
+              break;
+          case SIGALRM: if (kill(pid, SIGTERM) == 0)
+                        fprintf(stderr, "5 seconds over,child killed\n");
+                        }
+}
+ $ cc killprocess.c $ a.out  date Sat Jun 20  22:29:27  IST 2013
+Child dies: exit status: 0
+Parent dies 
+$ a.out find /home -name a.out -print /home /sumit/personal/project8/a.out
+/home/sumit/personal/books_code/glass_ables/12/a.out
+/home/sumit/personal/books_code/stevens_c/ch08/a.out  ..after 5 second time interval ...
+5 seconds over, child killed
+Parent dies
+ 
+
+
+$ 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)
-- 
cgit