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7.239. strace

Updated strace packages that fix two bugs and add one enhancement are now available for Red Hat Enterprise Linux 6.
The strace packages provide a utility to intercept and record the system calls called and received by a running process. The strace utility can print a record of each system call, its arguments and its return value. The strace utility is useful for diagnosing, debugging and instructional purposes.

Bug Fixes

BZ#759569
Prior to this update, the strace utility extracted arguments for the "semtimedop" system call from the wrong location on the IBM System z platforms. As a consequence, arguments for the "semtimedop" system call were incorrectly displayed. This update modifies strace to extract the arguments from the correct memory location so that the arguments for the "semtimedop" system call are displayed as expected.
BZ#837183
Prior to this update, the strace utility used special breakpoints to trace fork/vfork/clone system calls. As a consequence, sometimes strace could cause applications to crash when following fork/vfork/clone system calls. This update modifies strace to use PTRACE_SETOPTIONS to set the behavior at fork/vfork/clone system calls and applications no longer crash.

Enhancement

BZ#809917
Prior to this update, strace incorrectly decoded system calls when tracing a 32-bit process on a 64-bit machine, because strace on IBM System z platforms is not multi-arch aware. This update provides an additional strace executable (strace32) which can be used to trace 32-bit processes on 64-bit machines.
All users of strace are advised to upgrade to these updated packages, which fix these bugs and add this enhancement.