Issue with record help me plz

Hi all .
I want to ask your questions in this code :

exten=>s,n,Set(folder2=${soundsdir}monquanoel/ghiam)
exten=>s,n,System(mkdir -p ${folder2})
exten=>s,n,BACKTICKS(code,${scriptdir}getcode.pl ${CDR(userfield)} sv_monquanoel)
exten=>s,n,NoOp(${code})
exten=>s,n,Set(filekechuyen=${folder2}/${CALLERID(num)}_${code})

exten=>s,n(record),Record(${filekechuyen}:wav,5,20 0,s) ;(1)
exten=>s,n,Background(monquanoel/hd_nhacnho1) (2)

exten=>s,n(hd_4_12),Background(monquanoel/hd_4_12) ;(3)

if the command line (1) is excute i want to :
excute (2) : if silence in 5 second
excute (3) : if press # button

In (1) i mute mic but the system is saved record sound . I think (1) is skip recording if the line is not yet answered.

anyone help me plz

thanks a lot

What is the BACKTICKS application you reference?