catch

[bebig]

hi,
I am trying "catch" command.
========================================
set readFileInput [open testA1.txt" "r"]

If the file does not exist, the errors occur. how to start catch statment??

this is what I am thinking.

set retval [catch $readFileInput]

if {$retval != 1} {
puts "An error occurred"
}

Thank you in advance

 

[marsd]

No, you are thinking one step too late.
try-

proc openFile {name {opt "r"}} {

          if {[catch {set fd [open $name $opt]} err]} {
              puts $"error: $err"
              return -1
          }
          return $fd
}

HTH