Explain what the kernel must provide for a user-level implementation of threads, such as Java on UNIX.
What will be an ideal response?
A thread that makes a blocking system call provides no opportunity for the user-level scheduler to intervene, and so all threads become blocked even though some may be in the READY state. A user-level implementation requires (a) non-blocking (asynchronous) I/O operations provided by the kernel, that only initiate I/O; and (b) a way of determining when the I/O has completed -- for example, the UNIX select system call. The threads programmer should not use native blocking system calls but calls in the threading API which make an asynchronous call and then invoke the scheduler.
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a. line feed b. newline c. line marker d. startling
Software that searches the Web and sends information back to a search engine is known as a ____.
A. directory B. robot C. meta D. keyword
Use the ________ dialog box to add a table to the query design workspace
Fill in the blank(s) with correct word
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Answer the following statement true (T) or false (F)