запомнить введенные цифры в переменную

exten => 999,1,Read(myvar,myfile)

pro-sip*CLI> core show application read

-= Info about application 'Read' =-

[Synopsis] Read a variable.

[Description] Reads a #-terminated string of digits a certain number of times from the user in to the given <variable>. This application sets the following channel variable upon completion: ${READSTATUS}: This is the status of the read operation. OK ERROR HANGUP INTERRUPTED SKIPPED TIMEOUT

[Syntax] Read(variable[,filename[&filename2[&...]][,maxdigits[,options[,attempts[,timeout]]]]])

[Arguments] variable The input digits will be stored in the given <variable> name. filename file(s) to play before reading digits or tone with option i maxdigits Maximum acceptable number of digits. Stops reading after <maxdigits> have been entered (without requiring the user to press the '#' key). Defaults to '0' - no limit - wait for the user press the '#' key. Any value below '0' means the same. Max accepted value is '255'. options s: to return immediately if the line is not up.

i: to play  filename as an indication tone from your "indication
s.conf".

n: to read digits even if the line is not up.

attempts If greater than '1', that many <attempts> will be made in the event no data is entered. timeout The number of seconds to wait for a digit response. If greater than '0', that value will override the default timeout. Can be floating point.

[See Also] SendDTMF()