Richard Suchenwirth 2006-01-23 - In my series of mini-tools for eTcl, here's an approximation to the more tool to display one file in a text window read-only. The whole file is not read at once, but on demand: initially, and each time you press <Down>, a screenful (approximately - for long lines their extent is estimated) is loaded and displayed at end. The window is shortlived - once it loses focus, it gets destroyed.
proc more filename {
set f [open $filename]
catch {wce siphide} ;# hide keyboard
set w [toplevel .[clock clicks]]
wm title $w [file tail $filename]
bind $w <FocusOut> "catch {close $f}; destroy $w"
bind $w <Up> "$w.t yview scroll -1 page"
bind $w <Down> "more'page $w.t $f; $w.t yview scroll 1 page"
text $w.t -wrap word -height 20 -width 38
$w.t tag config blue -foreground blue
grid $w.t -sticky news
more'page $w.t $f
focus -force $w
}#-- Page presentation
proc more'page {t f} {
if [eof $f] return
set nmax 20
set n 0
$t config -state normal
while {[gets $f line]>=0} {
$t insert end $line\n
set ln [expr {[string length $line]/38+1}]
if {[incr n $ln]>$nmax} break
}
$t insert end [expr {[eof $f]? "EOF": "more..\n"}] blue
$t config -state disabled
}See IDE: from cathedral to patchwork bazaar for what I do this for.