OSF DCE Application Development Guide--Core Components

Chapter 8. Programming with Threads
This chapter discusses issues you face when writing a multithreaded program and how to
deal with those issues.
The topics discussed in this chapter are as follows:
• Calling UNIX services
• Using signals
• Nonthreaded libraries
• Avoiding nonreentrant software
• Avoiding priority inversion
• Using synchronization objects
• Signaling a condition variable
8.1 Calling UNIX Services
On a UNIX system that does not have kernel support for threads, making system and
library calls from within a multithreaded program raises the following issues:
• System calls may not be thread-reentrant.
• If a system call blocks, it blocks the entire process instead of blocking the calling
thread only.
8.1.1 Jacket Routines
To resolve the previous two issues, DCE Threads provides jacket routines for a number
of UNIX system calls. Threads call the jacket routine instead of the UNIX system
service; this allows DCE Threads to take action on behalf of the thread before or after
calling the system service. For example, the jacket routines ensure that only one thread
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