Right click in any window and click "Scan A File". Select the file you wish to scan, then enter the text you want to scan for.

alias ScanFile {
  window -aEk0 @Scan`File
  clear @Scan`File
  set %fname " $+ $sfile(C:\,Select A File To Scan,Scan) $+ "
  If (. isin $left(%fname,4)) {
    set %temp3 $left(%fname,3) 
    rename %fname $replace(%fname,$left(%fname,3),txt)
  }
  set %text $$?="Text To Find?"
  set %text2 $read(%fname, w, * $+ %text $+ *)
  set %read.number $readn
  set %begin.read.number $calc(%read.number - 10)
  set %end.read.number $calc(%read.number + 10)
  set %total.read.number %begin.read.number $+ - $+ %end.read.number
  loadbuf %total.read.number @Scan`File %fname
  inc %read.number 1
  start1234
}
alias start1234 {
  set %yn $?!="Read Next Set Of Text?"
  If (%yn = $false) { halt }
  If (%yn = $true) {
    If (!$read(!%fname, w, * $+ %text $+ *, %read.number) { echo @Scan`File There Are No Matche(s) Found. | halt }
    unset %yn
    clear @Scan`File
    set %text2 $read(%fname, w, * $+ %text $+ *, %read.number)
    set %read.number $readn
    set %begin.read.number $calc(%read.number - 10)
    set %end.read.number $calc(%read.number + 10)
    set %total.read.number %begin.read.number $+ - $+ %end.read.number
    loadbuf %total.read.number @Scan`File %fname
    inc %read.number 1
  }
  set %yn $?!="Read Next Set Of Text?"
  If (%yn = $false) { halt }
  If (%yn = $true) {
    If (!$read(%fname, w, * $+ %text $+ *, %read.number)) {
      halt
    }
    If ($read(%fname, w, * $+ %text $+ *, %read.number)) {
      start1234
    }
  }
  rename %fname $replace(%fname,$left(%fname,3),%temp3
  unset %yn %fname %read.number %total.read.number %read.number %end.read.number %begin.read.number %text %text2 %temp3
}
menu * {
  Scan A File:/scanfile
}