TCL Interview Questions and Answers – 4

TCL Scripts examples with sample programs
1.how to increment eacl element in a list ? eg: incrlist {1 2 3} =>2 3 4
set list1 {1 2 3}
set list2 {}
foreach i $list1 {
lappend list2 [expr {$i+1}] }
puts $list2
o/p:
2 3 4
2.How do you find the length of a string without using string length command in TCL
set var “welcome”
set list1 [split $var ""]
foreach i $list1 {
incr len }
puts $len
o/p:
7
3.How to extract “information” from “ccccccccaaabbbbaaaabbinformationabcaaaaaabbbbbbbccbb”
in tcl using a single command
puts [string trim "ccccccccaaabbbbaaaabbinformationabcaaaaaabbbbbbbccbb" "abc"]
o/p:
information
4.How to Swap 30 & 40 in IP address 192.30.40.1 using TCL script
set var “192.30.40.1″
set list1 [split $var "."]
set list2 [lreplace $list1 1 2 40 30]
set result [join $list2 "."]
puts $result
o/p:
192.40.30.1
5.Set ip address as 10.30.20.1 write a script to replace the 30 with 40
set var “10.30.20.1″
regsub 30 $var 40 result
puts $result
o/p:
10.40.20.1
6.How do you check whether a string is palindrome or not using TCL script
proc palindrome {str} {
set l [string length $str]
set i 0
incr l -1
set flag 0
while {$l>=0} {
set s [string index $str $i]
set e [string index $str $l]
if {$s==$e} {  } else {
set flag 1
break }
incr l -1
incr i 1
}
if {$flag ==0} { puts “The given string $str is palindrome” } else {
puts “The given string $str is not palindrome” }
}
palindrome “malayalam”
palindrome “welcome”
o/p:
The given string malayalam is palindrome
The given string welcome is not palindrome