Is there is a way of sourcing csh file in tcl script and bringing variables to the main shell?

I'm trying to source a some.cshrc during TCL script execution. I get no error but the variables set in some.cshrc are not passed back to the shell.

When writing it like: source some.cshrc I'm getting an error. Then I tried: exec /bin/csh -c "source some.cshrc"

Please advise

Solution

Since Csh and Tcl are two completely different languages, you cannot simply load a Csh file in a Tcl script via a source command.

You can think of a workaround instead. Let us assume you want to load all the variables set with a setenv command. Example contents of some.cshrc file could look something like this:

setenv EDITOR vim
setenv TIME_STYLE long-iso
setenv TZ /usr/share/zoneinfo/Europe/Warsaw

You can write a Tcl script which reads this file line by line and searches for setenv commands. You can then reinterpret the line as a list and set an appropriate variable in a global namespace via an upvar command.

#!/usr/bin/tclsh

proc load_cshrc {file_name} {
  set f [open $file_name r]
  while {[gets $f l] >= 0} {
    if {[llength $l] == 3 && [lindex $l 0] eq "setenv"} {
      upvar [lindex $l 1] [lindex $l 1]
      set [lindex $l 1] [lindex $l 2]
    }
  }
  close $f
}

load_cshrc "some.cshrc"
puts "EDITOR = $EDITOR"
puts "TIME_STYLE = $TIME_STYLE"
puts "TZ = $TZ"

Please note, that since we do not run a Csh subshell any variable substitutions in the Csh script would not occur.