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1.211.  strace

1.211.1.  RHBA-2009:0309: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2009:0309
An updated strace package that fixes a bug is now available.
The strace program intercepts and records the system calls that are made and the signals that are received by processes.
This updated strace package fixes a bug which occurred when "strace -f" was used to trace a multithreaded program. strace selected threads to trace in an inoptimal manner, which could have caused certain threads to either run more slowly or to perpetually wait. With this update, strace selects threads to trace in a smarter manner, thus ensuring that no threads are left overlong in a waiting state, and therefore resolving the issue.
All users of strace are advised to upgrade to this updated package, which resolves this issue.

1.211.2.  RHBA-2009:0017: bug fix update

Note

This update has already been released (prior to the GA of this release) as errata RHBA-2009:0017
Updated strace packages that fix one bug are now available.
The strace program intercepts and records the system calls that are made and the signals that are received by processes.
The following issue has been addressed:
  • when a stopped process being examined by strace is killed, strace now reports the event correctly. The prime example is a SIGKILL being sent to a traced process.
Users of strace should upgrade to these updated packages, which resolves this bug.

1.211.3.  RHBA-2009:1317: bug fix update

An strace update that fixes several bugs is now available.
The strace program intercepts and records system calls issued and received by a running process. Strace can print a record of each system call, its arguments and its return value.
With this update, strace is now upgraded to version 4.5.18. This applies several upstream bug fixes and enhancements, including:
  • An erroneous file locking instruction caused strace to incorrectly decode fcntl64() system call parameters in 32-bit programs running on 64-bit systems. This release corrects the errant file locking instruction, ensuring that fcntl64() system call parameters are decoded correctly. (BZ#471169)
  • A race condition made it possible for ptrace_do_wait() to prematurely conclude an exit report of a terminated process before the kill signal could set the proper exit code. Whenever this occurred, strace could leave out details of the kill signal in its exit report. This update applies a workaround that instructs strace to check SIGKILL queues before issuing an exit report. (BZ#472053)
  • When strace was executed with the -f option on a multi-threaded process, it was possible for some threads in that process to stop. This could prevent the traced process from terminating. This was caused by a bug that prevented some threads in a traced multi-threaded process from receiving ample CPU time. This update provides functions for providing CPU time to threads in traced multi-threaded processes, along with instructions for resuming halted threads. (BZ#478419)
Users of strace should apply this update.

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