1thr_min_stack(3C) Standard C Library Functions thr_min_stack(3C)
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6 thr_min_stack - return the minimum-allowable size for a thread's stack
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9 cc -mt [ flag... ] file...[ library... ]
10 #include <thread.h>
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12 size_t thr_min_stack(void);
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16 When a thread is created with a user-supplied stack, the user must
17 reserve enough space to run this thread. In a dynamically linked execu‐
18 tion environment, it is very hard to know what the minimum stack
19 requirments are for a thread. The function thr_min_stack() returns the
20 amount of space needed to execute a null thread. This is a thread that
21 was created to execute a null procedure. A thread that does something
22 useful should have a stack size that is thr_min_stack() + <some incre‐
23 ment>.
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26 Most users should not be creating threads with user-supplied stacks.
27 This functionality was provided to support applications that wanted
28 complete control over their execution environment.
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31 Typically, users should let the threads library manage stack alloca‐
32 tion. The threads library provides default stacks which should meet the
33 requirements of any created thread.
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36 thr_min_stack() will return the unsigned int THR_MIN_STACK, which is
37 the minimum-allowable size for a thread's stack.
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40 In this implementation the default size for a user-thread's stack is
41 one mega-byte. If the second argument to thr_create(3C) is NULL, then
42 the default stack size for the newly-created thread will be used. Oth‐
43 erwise, you may specify a stack-size that is at least THR_MIN_STACK,
44 yet less than the size of your machine's virtual memory.
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47 It is recommended that the default stack size be used.
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50 To determine the smallest-allowable size for a thread's stack, execute
51 the following:
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53 /* cc thisfile.c -lthread */
54 #define _REENTRANT
55 #include <thread.h>
56 #include <stdio.h>
57 main() {
58 printf("thr_min_stack() returns %u\n",thr_min_stack());
59 }
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63 See attributes(5) for descriptions of the following attributes:
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68 ┌─────────────────────────────┬─────────────────────────────┐
69 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
70 ├─────────────────────────────┼─────────────────────────────┤
71 │MT-Level │MT-Safe │
72 └─────────────────────────────┴─────────────────────────────┘
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75 attributes(5), standards(5)
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79SunOS 5.11 12 May 1998 thr_min_stack(3C)