Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
12 years ago

Backspace character in System Console

I am testing some memory using System Console and I would like to make a simple progress bar which will show current progress. For that I would need a backspace character.

The Tcl interpreter from Centos 7 works as expected: 


$ tclsh
% puts $tcl_version
8.5
% puts "abc\bd"
abd

But System Console gives this: 


% puts $tcl_version
8.5
% puts "abc\bd"
abcd

Is there any way I can delete current characters or maybe whole line in System Console?

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    Probably not. System Console is a very crippled console interface which I believe is based on Jacl (a Java TCL interpreter).

    You might be better off looking at the Dashboard widgets and see if you can use a progress indicator there.

    Cheers,

    Dave
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    12 years ago

    The solution is so simple that I am almost ashamed to post it. You don't have to delete anything if you dont print anything, so for a very simple progress bar it is enough to print a character on the right iterations.

    Here is the code: 

    
set BAR_LEN 50
# ##############################################################################
#  Puts top line
proc put_top_line { } {
	global BAR_LEN	
	puts -nonewline "|"
	for {set i 0} {$i < $BAR_LEN} {incr i} {
		puts -nonewline "-"
	}
	puts -nonewline "|\n"
}
# ##############################################################################
#  Puts#  to fill the progress bar, should be called every loop iteration
proc put_filler {cur max} {
	global BAR_LEN	
	if {  } { 
		puts -nonewline "|"
	} elseif {  } { 
		puts -nonewline "|\n"
	} else {
		set curValue 
		set nextValue 
		if {  } {
			puts -nonewline "#"
		}
	}	
}
# ##############################################################################
#  Test
put_top_line
for {set i 0} { $i < 1000 } { incr i } {
	put_filler $i 999
	after 10
}