88 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
			
		
		
	
	
			88 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
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<html>
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<head>
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<title>usemtest</title>
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<link rel="stylesheet" type="text/css" media="all" href="../man.css">
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</head>
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<body bgcolor=#ffffff>
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<h2 align=center>usemtest</h2>
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<h4 align=center>OS/161 Reference Manual</h4>
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<h3>Name</h3>
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<p>
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usemtest - test semfs (<tt>sem:</tt>) semaphores
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</p>
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<h3>Synopsis</h3>
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<p>
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<tt>/testbin/usemtest</tt>
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</p>
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<h3>Description</h3>
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<p>
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<tt>usemtest</tt> forks some subprocesses and uses the semfs
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semaphores to do coordinated printing. It is somewhat similar to the
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<tt>sy1</tt> in-kernel test for the in-kernel semaphores.
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</p>
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<p>
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The first parts of the test open each semaphore separately in each
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process, so locking issues in the filetable and open-file code should
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not keep it from running.
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The last part opens the semaphores once and inherits the file
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descriptors through fork; it is likely to hang (including sometimes in
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fork) if the filetable and open-file locking is not just so.
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</p>
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<h3>Requirements</h3>
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<p>
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<tt>usemtest</tt> uses the following system calls:
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<ul>
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<li> <A HREF=../syscall/fork.html>fork</A>
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<li> <A HREF=../syscall/open.html>open</A>
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<li> <A HREF=../syscall/read.html>read</A>
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<li> <A HREF=../syscall/read.html>remove</A>
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<li> <A HREF=../syscall/waitpid.html>waitpid</A>
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<li> <A HREF=../syscall/write.html>write</A>
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<li> <A HREF=../syscall/_exit.html>_exit</A>
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</ul>
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</p>
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<p>
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<tt>usemtest</tt> should run successfully once the basic system calls
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are complete.
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Until you implement the <tt>remove()</tt> system call the semaphores
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from the test will be left lying around afterwards, but this should
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not keep it from running.
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</p>
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</body>
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</html>
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