dbx is a tool for source-level debugging and execution of programs. It allows you to determine the exact statement that caused a core dump, or to monitor the. A Short User Manual for dbx. “dbx” is the name of the debugger that is available for use on many Unix systems. This document is intended to list the most. There is a fancier X-windows interface for AIX, invoked with the command xde, The dbx debugger is able to track the execution of your program line-by-line in the first at the file containing the main program and is waiting for instructions.
If the screen subcommand is issued in a non-Xwindow environment, the dbx program displays a warning message and resumes debugging as if the screen subcommand was not given. See clear subcommand, the delcmd subcommand, the delete subcommand, disable subcommand, enable subcommand, the stop subcommand, the status subcommand, and the trace subcommand. Changing the current function implicitly changes the current source file to the file containing the new function; the current scope used for name resolution is also changed.
Directories in the list are evaluated in the order specified. Otherwise, the debug program is entered and the reason for termination is reported.
Indicates the priority of the kernel thread. The default is to look for source files in the following directories: Begins execution of an application with the previous arguments. To avoid this, the previous event must be deleted before creating a new one.
Indicates the clock attribute of a condition attribute object.
The tracei subcommand turns on tracing when:. Lists dbx subcommands for accessing program variables and data. If the more parameter is specified, the status subcommand also displays the dbx subcommands associated with the breakpoints, tracepoints, and watchpoints. The third form of the thread subcommand is used to control dbxx execution. This subcommand changes the value of the at sign variable. Specifies the display name for the X Window System, for use with the multproc subcommand or the screen subcommand.
The malloc subcommand with no options prints out a aic of enabled options and allocation policies as well as a statistical summary of malloc usage since process mqnual. To turn on vi-style command line editing, you would type the subcommand set edit vi or set -o vi.
It also displays the active trace, stop subcommands, and the remaining thread tskip counts. A breakpoint set on a source line or function is hit by any user thread which executes the line or function, unless you specify conditions as in example 9.
Analyzing core Dumps with the dbx Command in AIX
All the threads are run during this operation. The String parameter is a series of dbx subcommands that, after the execution of this subcommand, can be referred to by Name.
The newpath variable specifies what it is to be replaced with. Indicates the state of the user thread. Manhal the next line to be displayed. The following operators are valid in expressions: The default is a. To call a command while running the dbx command, enter:. The delete subcommand removes traces and stops from the application program and tskip counts for a thread. If the system does not have the X Window System support, a warning message is issued when the debugger forks, and the dbx program zix debugging only the parent process.
Continues application program execution from the current stopping point until the program finishes or another breakpoint is encountered. Using an optional attribute RELOP value argument allows for a more narrow selection of active allocations.
The value can be yes or no. Turns off subscript checking on arrays. The goto subcommand causes the specified source line to manial run next.
The dbx debugger
This pertains to four dbx subcommands: Lists instructions from the application program. Display the full qualification of an identifier Parent topic: The alternative object file can be specified only while attaching to a process. Holds all threads except the running thread during the contnextnextiand step subcommands. The executable-file argument is an load module produced by a compiler. The info option produces more detailed output about a thread, from the user thread structure.
The remaining tskip count, which was set using the tskip subcommand for a thread, can be deleted using the tskip flag. Specifies the abbreviated output mode, which consists of a single line for each loaded module containing the entry number, module name, and optional member name for that module.
The following list contains possible values for the Expression parameter: Indicates the priority attribute of a thread attributes object. Displays lines of the current source file. Examples This example shows you how to attach dbx to a running process.
Indicates the protocol attribute of a mutex. To attach the debug program, you need authority to use the kill command on this process.