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Full Discussion: how exactly does pclose work in C?
Top Forums Programming how exactly does pclose work in C? Post 302504929 by lilezek on Tuesday 15th of March 2011 07:25:27 PM
Old 03-15-2011
It is easy, if no brackets are present, it means it only executes one instruction (or block) just after that line. That means:

Code:
for a hundred of times
{
     cout << "foo";
     cout << "bar" << endl;
}

You will see 100 times foobar

Code:
for a hundred of times
      cout << "foo";
cout << "bar" << endl;

You'll see 100 times foo and once bar at the end.

and:

Code:
for (last = NULL, cur = pidlist; cur; last = cur, cur = cur->next)

Means:

At start, we define last to be NULL and cur to be pidlist.
The for loop will continue while cur is != 0, that is, while (bool)cur is true.

At end of EACH LOOP, it defines last to be cur, and cur to be the next member of cur.

This is an usual way to loop through an structure of nodes. A node is an structure that knows who structure is next and who is last.

So the loop starts on cur, goes ->next, goes ->next, and ->next... until cur = cur->next is NULL. That is, there is no next after this.

I hope that is a bit helpful for you.
 

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LEARN ABOUT MOJAVE

isalist

isalist(1)                                                         User Commands                                                        isalist(1)

NAME

       isalist - display the native instruction sets executable on this platform

SYNOPSIS

       isalist

DESCRIPTION

       isalist  prints  the names of the native instruction sets executable on this platform on the standard output, as returned by the SI_ISALIST
       command of  sysinfo(2).

       The names are space-separated and are ordered in the sense of best performance. That is, earlier-named instruction sets  may  contain  more
       instructions  than  later-named  instruction  sets;  a  program that is compiled for an earlier-named instruction sets will most likely run
       faster on this machine than the same program compiled for a later-named instruction set.

       Programs compiled for instruction sets that do not appear in the list will most likely experience performance degradation or not run at all
       on this machine.

       The  instruction  set  names  known to the system are listed in  isalist(5).  These names may or may not match predefined names or compiler
       options in the C language compilation system,

ATTRIBUTES

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

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE         |      ATTRIBUTE VALUE        |
       |Availability                 |SUNWcsu                      |
       +-----------------------------+-----------------------------+

SEE ALSO

       optisa(1), uname(1), sysinfo(2), attributes(5), isalist(5)

SunOS 5.10                                                          25 Jul 1997                                                         isalist(1)
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