STREAMS/UX for the HP 9000 Reference Manual

129
Debugging STREAMS/UX Modules and Drivers
STREAMS/UX Debugging Tool
qh Command
Enter the qh command to see a stream head read queue. Enter the driver
name and minor number to specify the stream head read queue to display.
An example is shown below. When strdb prints the stream head read queue,
you are put in primary mode. This lets you enter navigation commands to
look at data structures pointed to by fields in the queue. These navigation
commands are described below under “Primary Commands.”
qh tmx 0
struct queue 0x584300 S:1
q_qinfo = 0x2944f0 q_pad1[2] = 00
q_first = 0x0 q_other = 0x584374
q_last = 0x0
q_next = 0x0
q_link = 0x0
q_ptr = 0x5f8500
q_count = 0
q_flag = 0x1029
QREADR
QWANTR
QUSE
QSYNCH
q_minpsz = 0
q_maxpsz = -1
q_hiwat = 0x200
q_lowat = 0x100
q_bandp = 0x0
q_nband = 0
q_pad1[0] = 00
q_pad1[1] = 00
Primary Commands
strdb provides two types of primary mode commands. One kind is used to
navigate through data structures. The other kind changes the characteristics
of the strdb session.
Data Structure Navigation Commands
When you enter the qh command, strdb prints the stream head read queue
and puts you in primary mode. You can enter navigation commands to look
at data structures pointed to by fields in the queue. Note that primary mode
does not prompt you for commands; you just enter the command keys. You
do not need to enter a carriage return with navigation commands. In the
example below, a ? is entered to see which fields strdb can format. strdb