Y must be a simple character scalar or vector which is taken to be the name of a visible defined function or operator.

Note that ⎕MONITOR does not apply to dfns or dops.

R is a simple non-negative integer matrix of 5 columns with one row for each line in the function or operator Y which has the monitor set, giving:

Column 1	Line number
Column 2	Number of times the line was executed
Column 3	CPU time in milliseconds
Column 4	Elapsed time in milliseconds
Column 5	Reserved

The value of 0 in column one indicates that the monitor is set on the function or operator as a whole. R will be empty for dfns and dops.

      ∇ FOO
[1]   A←?25 25⍴100
[2]   B←⌹A
[3]   C←⌹B
[4]   R1←⌊0.5+A+.×B
[5]   R2←A=C
      ∇
 
      (0,⍳5) ⎕MONITOR 'FOO' ⍝ Set monitor
 
      FOO                   ⍝ Run function
 
      ⎕MONITOR 'FOO'        ⍝ Monitor query
0 1 1418 1000 0
1 1   83    0 0
2 1  400    0 0
3 1  397    0 0
4 1  467 1000 0
5 1  100    0 0