Native Inspect Manual (H06.07+)

Introducing Native Inspect

Native Inspect Manual—528122-006

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Snapshot File Analysis

A process snapshot file or snapshot is a disk file that is an image of a process, its data,

and its status at the moment it was saved—analogous in function to “core” files on

UNIX systems. Snapshot files have file code 130. All three debuggers—Native Inspect,

Visual Inspect, and Inspect—can be used to debug snapshot files (Inspect refers to

snapshot files as save files).

Creating a Snapshot File

You can create snapshot files in several ways, such as:

•

Using the save command (Native Inspect)

•

Using the Save Snapshot command (Visual Inspect)

•

Using the SAVE command (Inspect)

Snapshot files are also created by the Snapshot server (INSPSNAP) if the

SAVEABEND attribute for a process is ON and the process abends.

Opening a Snapshot file

Use the Native Inspect snapshot command to open a snapshot file, providing a read-

only view of the state of the process that the snapshot represents.

To open a snapshot file, start Native Inspect and then enter:

(eInspect 3,301): snapshot $disk3.mysubvol.myprog

where $disk3.mysubvol.myprog is the name of a TNS/E native snapshot file (file

code 130) located on the TNS/E system.

Considerations

•

You can examine only one snapshot file at a time, and you cannot debug a process

at the same time. You cannot execute any Native Inspect commands that would

alter the state of the snapshot, or commands that would execute a process, such

as step or continue. Such commands report an error during snapshot analysis.

•

If the snapshot was created in a different location from its present location, you

might need to manually load symbols for loadfiles (using the symbol command or

symbol-file command,) and set a source search path (using the dir command).

Debugging DLLs

Dynamic-link libraries (DLLs), which contain position-independent code (PIC), are the

standard user libraries on TNS/E systems. DLLs can be implicitly loaded by the system

when a program is started or explicitly loaded and unloaded by program calls to

dlopen() and dlclose(), respectively.