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1.134.  ltrace

1.134.1.  RHBA-2009:0380: bug fix update


This update has already been released (prior to the GA of this release) as FASTRACK errata RHBA-2009:0380
An updated ltrace package that fixes various bugs is now available.
The ltrace utility is a debugging program that runs a specified command until the command exits. While the command is executing, ltrace intercepts and records both the dynamic library calls called by the executed process and the signals received by the executed process. The ltrace utility can also intercept and print system calls executed by the process.
This updated ltrace package includes fixes for the following bugs:
  • in some cases, when tracing the process that used fork system call, the kernel may have reported certain events in the forked child even before it reported that the fork had occurred in the first place. With this update, ltrace now anticipates this behavior, thus resolving the issue.
  • on IBM System z machines, ltrace would crash when attempting to trace binaries that called functions with five or more arguments. This has been fixed with this update and ltrace now works as expected.
  • when ltrace's '-o' option, which writes the output to a file, was used alongside the '-c' option, which counts time and calls for each library call and reports a summary, ltrace sent the output to standard error as usual instead of to the file designated on the command line. With this updated package, ltrace sends the output to the designated file when it is called with the '-c' option, thus resolving this issue.
  • ltrace was not able to trace a binary that was called using the "exec" system call. With this update, ltrace is now able to do so.
  • the ltrace(1) man page incorrectly claimed that ltrace could not trace 64-bit binaries, and has been corrected.
  • a bug in which ltrace would become unresponsive (i.e. "hang") while tracing a child process with the '-f' option, which traces child processes as they are created by currently traced processes as a result of the fork or clone system calls. To correct for this, ltrace now tests for the situation in which it fails to attach to a newly-forked process, thus resolving the issue.
All users of ltrace are advised to upgrade to this updated package, which resolves these issues.

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