In column number 30 of the NC program, the post function (psof) that generated the code is displayed.  On some lines you'll see two post functions.  NC block N104 shows  "psof ptool-call".  This means that "psof" called "ptool-call" to output this line of code.

N100G20                        psof
N102G0G17G40G49G80G90         psof
(1" FLAT ENDMILL TOOL1 DIA 1.000)  psof ptoolcomment
(DIA OFFSET D1 LEN OFFSET H1)  psof ptoolcomment
(ROUGH MILL)             psof pcomment2
N104T1M6                    psof ptool-call
N106T2                         psof ptool-call
N108S534M3               psof
N110G0G90G54X-1.4526Y-1.416   psof
N112G43H1Z.25M8    psof
N114Z.1                        pzrapid prapidout
N116G1Z-1.02F6.42   plin plinout
N118X-.9526Y-.55       plin plinout