detect Magic question

DETECT MAGIC reads:

Magic-User Level 1
Duration: Instantaneous
Range: Line of Sight
This spell allows the caster to know if
anything within his field of vision (or on
his person) is in any way magical. This
includes magical creatures, magical items,
or any creature or object under the effect
of an ongoing spell. Spellcasters such as
Magic-Users and Elves do not detect as
magic with this spell, but anyone that is
under the effects of an active spell does.
The spell does not identify the nature of
the magic, only that magic is present.
The caster must already be able to see
the object in question in order to detect it
as magical. Concealed, covered, or
invisible objects will not be revealed by
this spell.

Does this allow the caster to cast the spell then, for example, look all around the room, detecting all magic items within a diameter with the caster at the center.