crashpad/tools/mac/catch_exception_tool.md

catch_exception_tool(1)

Name

catch_exception_tool—Catch Mach exceptions and display information about them

Synopsis

catch_exception_tool -m SERVICE [OPTION…]

Description

Runs a Mach exception server registered with the bootstrap server under the name SERVICE. The exception server is capable of receiving exceptions for “behavior” values of EXCEPTION_DEFAULT, EXCEPTION_STATE, and EXCEPTION_STATE_IDENTITY, with or without MACH_EXCEPTION_CODES set.

Options

• -f, --file=FILE

  Information about the exception will be appended to FILE instead of the standard output stream.

• -m, --mach-service=SERVICE

  Check in with the bootstrap server under the name SERVICE. This service name may already be reserved with the bootstrap server in cases where this tool is started by launchd(8) as a result of a message being sent to a service declared in a job’s MachServices dictionary (see launchd.plist(5)). The service name may also be completely unknown to the system.

• -p, --persistent

  Continue processing exceptions after the first one. The default mode is one-shot, where this tool exits after processing the first exception.

• -t, --timeout=TIMEOUT

  Run for a maximum of TIMEOUT seconds. Specify 0 to request non-blocking operation, in which the tool exits immediately if no exception is received. In --persistent mode, TIMEOUT applies to the overall duration that this tool will run, not to the processing of individual exceptions. When --timeout is not specified, this tool will block indefinitely while waiting for an exception.

• --help

  Display help and exit.

• --version

  Output version information and exit.

Examples

Run a one-shot blocking exception server registered with the bootstrap server under the name svc:

$ catch_exception_tool --mach-service=svc --file=out &
[1] 1233
$ exception_port_tool --set-handler=handler=bootstrap:svc crasher
Illegal instruction: 4
[1]+  Done    catch_exception_tool --mach-service=svc --file=out
$ cat out
catch_exception_tool: behavior EXCEPTION_DEFAULT|MACH_EXCEPTION_CODES, pid 1234, thread 56789, exception EXC_CRASH, codes[2] 0x4200001, 0, original exception EXC_BAD_INSTRUCTION, original code[0] 1, signal SIGILL

Run an on-demand exception server started by launchd(5) available via the bootstrap server under the name svc:

$ `on_demand_service_tool --load --label=catch_exception \
      --mach-service=svc \
      $(which catch_exception_tool) --mach-service=svc \
      --file=/tmp/out --persistent --timeout=0
$ exception_port_tool --set-handler=handler=bootstrap:svc crasher
Illegal instruction: 4
$ on_demand_service_tool --unload --label=catch_exception
$ cat /tmp/out
catch_exception_tool: behavior EXCEPTION_DEFAULT|MACH_EXCEPTION_CODES, pid 2468, thread 13579, exception EXC_CRASH, codes[2] 0x4200001, 0, original exception EXC_BAD_INSTRUCTION, original code[0] 1, signal SIGILL

Exit Status

• 0

  Success. In --persistent mode with a --timeout set, it is considered successful if at least one exception was caught when the timer expires.

• 1

  Failure, with a message printed to the standard error stream.

See Also

exception_port_tool(1), on_demand_service_tool(1)

Resources

Crashpad home page: https://crashpad.chromium.org/.

Report bugs at https://crashpad.chromium.org/bug/new.

Copyright

Copyright 2014 The Crashpad Authors.

License

Licensed under the Apache License, Version 2.0 (the “License”); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.