summaryrefslogtreecommitdiff
path: root/reference/C/FUNCTIONS/fork.html
blob: 06014234e3b4bdbfe7346d4a73ae19746ae6b801 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
<title>fork function</title>
<head>
<script language="JavaScript">
</script>
</head>
<body bgcolor="#ffffcc">
<hr>
<center>
<h1>fork function </h1>
</center>
<hr>
<b>fork</b> spawns a copy of the running process. The copy (or child) 
has a copy of the parent process stack, data area and heap and starts 
execution after the fork statement. fork is of use when you wish to 
write daemon processes.
<p>
<hr>
<center>
<table border=2 width="80%" bgcolor="ivory">
<tr>
<td width="80%">
<pre>

	Library:   unistd.h

	Prototype: pid_t fork(void);

	Syntax:    pid_t PID

                   PID = fork();
</pre>
</td>
</tr>
</table>
</center>
<p>
On completion, PID will have one of the following values:

<pre>
 > 0 == the childs process ID.
   0 == is returned to the child process.
 < 0 == an error occoured. No child created, errno is set to 
        indicate the problem
</pre>
<hr>
<h2>Examples:</h2>

<img src="../../GRAPHICS/computer.gif"><a href="../EXAMPLES/fork1.c"> example</a> 
program.

<hr>
<h2>See Also:</h2>

<img src="../../GRAPHICS/whiteball.gif">
<a href="pipe.html">pipe function.</a><p>

<img src="../../GRAPHICS/whiteball.gif">
<a href="execl.html">execl function.</a><p>

<img src="../../GRAPHICS/whiteball.gif">
<a href="../glossary.html#threads">threads</a><p>


<p>

<hr>
<p>
<center>
<table border=2 width="80%" bgcolor="ivory">
<tr align=center>
<td width="25%">
<a href="../cref.html">                  Top</a>
</td><td width="25%">
<a href="../master_index.html">          Master Index</a>
</td><td width="25%">
<a href="../SYNTAX/keywords.html">                 Keywords</a>
</td><td width="25%">
<a href="funcref.htm">      Functions</a>
</td>
</tr>
</table>
</center>
<p>
<hr>
<address>Martin Leslie 
</address><p>
</body>
</html>