User`s guide

38 Agilent VISA User’s Guide
3 Programming with VISA
The parameters are defined as follows.
The handle returned from viFindRsrc should be closed to free up all the
system resources associated with the search. To close the find object,
pass the findList to the viClose function.
Use the expr parameter of viFindRsrc to specify the interface to search.
You can search for devices on the specified interface. Use the following
table to determine what to use for your expr parameter.
Table 9 Definitions of Parameters
Parameter Description
sesn The resource manager session.
expr The expression that identifies what to search (Table 10).
findList A handle that identifies this search. This handle will then be
used as an input to the viFindNext function when finding
the next match.
retcnt A pointer to the number of matches found.
instrDesc A pointer to a string identifying the location of the match.
Note that you must allocate storage for this string.
NOTE
Because VISA interprets strings as regular expressions, the string
GPIB?*INSTR applies to both GPIB and GPIB-VXI devices.
Table 10 Determining What to Use for the expr Parameter
Interface expr Parameter
GPIB GPIB[0-9]*::?*INSTR
VXI VXI?*INSTR
GPIB-VXI GPIB-VXI?*INSTR
GPIB and GPIB-VXI GPIB?*INSTR
All VXI ?*VXI[0-9]*::?*INSTR
ASRL ASRL[0-9]*::?*INSTR
All ?*INSTR