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Full Discussion: fork system call understanding
Homework and Emergencies Homework & Coursework Questions fork system call understanding Post 302400114 by karthigayan on Tuesday 2nd of March 2010 08:29:03 AM
Old 03-02-2010
MySQL Explanation
Normally when we use fork the child will inherit the workspace of the parent.And also the child and the parent will run simultaneously.and any one can finish its process first.

Now come to your doubt,

Your while loop runs twice.Beginning of the loop you print some thing like " before fork():getpid()= 6010 " .When the first iteration a child process will get create.So the child and parent start to run simultaneously.So the statements can print in any order.

So the child have a provision the iterate the loop.So it will print the "before fork statement" .When the next iteration of the loop also the "bofore fork will get print.And the child process will get create and the appropriate statements will get print.

When the try for the next iteration the condition will get false.So it will come out.

Here :
One of the "before fork" statement is printed by the child process.
 

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LEARN ABOUT OPENSOLARIS

mktemp

mktemp(3C)						   Standard C Library Functions 						mktemp(3C)

NAME

       mktemp - make a unique file name  from a template

SYNOPSIS

       #include <stdlib.h>

       char *mktemp(char *template);

DESCRIPTION

       The  mktemp() function replaces the contents of the string pointed to by template with a unique file name, and returns template. The string
       in template should look like a file name with six trailing 'X's; mktemp() will replace the 'X's with a character string that can be used to
       create a unique file name. Only 26 unique file names per thread can be created for each unique template.

RETURN VALUES

       The mktemp() function returns the pointer template. If a unique name cannot be created, template points to a null string.

ERRORS

       No errors are defined.

EXAMPLES

       Example 1 Generate a filename.

       The  following example replaces the contents of the "template" string with a 10-character filename beginning with the characters "file" and
       returns a pointer to the "template" string that contains the new filename.

	 #include <stdlib.h>
	 ...
	 char *template = "/tmp/fileXXXXXX";
	 char *ptr;
	 ptr = mktemp(template);

USAGE

       Between the time a pathname is created and the file opened, it is possible for some other process to create a file with the same name.  The
       mkstemp(3C) function avoids this problem and is preferred over this function.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       mkstemp(3C), tmpfile(3C), tmpnam(3C), attributes(5), standards(5)

SunOS 5.11							    15 Sep 2004 							mktemp(3C)
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