Re: ?? exec prog << value ??



In article <DDD7i.6794$C96.2729@xxxxxxxxxxxxxxxxxxxxxxxxxx>,
Bryan Oakley <oakley@xxxxxxxxxxxxxxxxxxxx> wrote:
Zeh Mau wrote:
Hello comp.lang.tcl !!!

I have the following problem:

I have created a program with with flex and bison (lex, yacc),
a small calculator,
now i want to execute the program within a tcl-script.

Therefore I write

exec prog << var
where var shall be the mathematical expression, e.g. 2+2

Now I thought,
the prog will be executed and by using
<<
the value of var (string) 2+2 will be passed as input to prog.

Unfortunately, there is only
the message "syntax error" instead of - as i have expected - 4.

Show us the complete and actual error message, as well as the exact line
of code. Otherwise we can only guess.

In addition, also tell us what happens when you do "echo '2+2' | prog"
from the command line.
.
.
.
Possible variations that occur to me:

exec prog << $var

exec prog << $var\n

I can easily imagine, though, that

exec prog << var

tosses an exception.
.



Relevant Pages

  • Re: ?? exec prog << value ??
    ... where var shall be the mathematical expression, ... value of the variable var you have to use $var, ... exec prog << $var ...
    (comp.lang.tcl)
  • ?? exec prog << value ??
    ... a small calculator, ... now i want to execute the program within a tcl-script. ... where var shall be the mathematical expression, ... the prog will be executed and by using ...
    (comp.lang.tcl)
  • Re: ?? exec prog << value ??
    ... a small calculator, ... now i want to execute the program within a tcl-script. ... where var shall be the mathematical expression, ... the prog will be executed and by using ...
    (comp.lang.tcl)
  • Re: ?? exec prog << value ??
    ... a small calculator, ... now i want to execute the program within a tcl-script. ... the value of var 2+2 will be passed as input to prog. ...
    (comp.lang.tcl)
  • Re: ?? exec prog << value ??
    ... a small calculator, ... now i want to execute the program within a tcl-script. ... the value of var 2+2 will be passed as input to prog. ...
    (comp.lang.tcl)