z/OS V1R9.0 UNIX System Services Command ... - Christian Grothoff

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debugging. For example: dbx -p 9.123.456.78:8001 mypgm. In this mode
the command line prompt will not be displayed nor will the user be able to
enter dbx subcommands through the command line interface. In addition,
the following dbx subcommands are not supported when entered via a GUI
debug console (command line) interface: detach, edit, multproc, object,
quit, rerun, run, sh.
If :port is not specified, port 8001 will be used as the default.
–q Suppresses some of the dbx startup messages. Specifically, this will only
print the dbx version information before the prompt is displayed. All other
messages will be suppressed. Note that this option does not affect the
verbosity of normal dbx operation.
–r Runs the object file immediately. If it ends successfully, the dbx debug
program is exited. Otherwise, the debug program is entered and the reason
for termination is reported.
Note: Unless –r is specified, the dbx command prompts the user and waits
for a command. However, you can specify program arguments on
dbx even when –r is not used. For example:
dbx myprog arg1 arg2 arg3
–u Deprecated. This option will be ignored and remains only for compatibility
purposes.
Expression Handling
Specify expressions in dbx with a subset of C and Pascal syntax. A prefix *
(asterisk) or a postfix ^ (circumflex) denotes indirection. Specify portions of an array
by separating the lower and upper bounds with .. (two periods).
Use [ ] (square brackets) or ( ) (parentheses) to enclose array subscripts. Use the
field reference operator . (period) with pointers and records.
Note: The field reference operator . (period) makes the C operator → unnecessary
(although it is supported).
When displaying variables and expressions, the dbx command resolves names first
using the static scope of the current function. The dynamic scope is used if the
name is not defined in the first scope. If static and dynamic searches do not yield a
result, an arbitrary symbol is chosen and the system prints the message (using
Module.Variable). The Module.Variable construction is the name of an identifier
qualified with a block name. Override the name resolution procedure by qualifying
an identifier with a block name. Source files are treated as modules named by the
filename without the language suffix (such as the .c suffix on a C language
program).
The dbx command debug program checks types of expressions. Override types of
expressions by using TypeName (Expression). When there is no corresponding
named type, use the &TypeName special construct to represent a pointer to the
named type. Represent a pointer to enum, struct, or union tag with the
$$TagName construct.
A condition can be any dbx expression that evaluates to a true or false value. This
pertains to four dbx subcommands: stop, stopi, trace, and tracei.
dbx
Chapter 2. Shell command descriptions 185