Dear All,
I have a problem.
I try to execute a command line program from my Scheme program.
The stdout and stderr of the command line program should
be redirected to a text-field%. I have one program which
writes to stdout and stderr quite quickly and I get the
following error:
iproc.scm:79:24: sequence-contract-violation: negative: method insert cannot be
called, except in states (unlocked), args "iProc ERROR: Run Time: 0.00
seconds\r"
It seems, there is some problem with locking.
I also include the iproc.scm file, which executes the external
command line program.
What can I do to solve this problem???
Thanks for any help.
Best regards,
Peter Ivanyi
-------------------------------------------------
(module iproc scheme
(require (lib "process.ss")
(file "sx-alert.scm")
)
(provide iproc)
(define (iproc command editor)
(let
( (proc #f)
(proc-in #f)
(proc-out #f)
(proc-err #f)
(thd #f)
)
(begin
; For debugging
(display "Command: ")
(display command)
(newline)
; start the process asynchronously
(set! proc (process command))
; if we could start it
(if (and proc (eq? 'running ((list-ref proc 4) 'status)))
(begin
(set! proc-in (list-ref proc 0))
(set! proc-out (list-ref proc 1))
(set! proc-err (list-ref proc 3))
; a WATCHDOG thread to see whether the program is running
(set! thd (thread
(lambda ()
(dynamic-wind
void;
(lambda ()
; wait until the program is running
((list-ref proc 4) 'wait)
)
(lambda ()
;(display "SCM: finished watchdog\n")
(set! proc #f)
(close-output-port proc-out)
)
)
)
)
)
; OUTPUT from program
(thread
(lambda ()
(dynamic-wind
void
(lambda ()
(when editor
(do ((line (read-line proc-in) (read-line proc-in)))
((eof-object? line))
(if editor
(send editor insert line)
(sx-alert #f
"iProc ERROR"
(string-append "iProc ERROR: " line)
#f)
)
)
)
)
(lambda () (close-input-port proc-in)))))
; ERROR from program
(thread
(lambda ()
(dynamic-wind
void
(lambda ()
(do ((line (read-line proc-err) (read-line proc-err)))
((eof-object? line))
(if editor
(send editor insert (string-append "iProc ERROR: "
line))
(sx-alert #f
"iProc ERROR"
(string-append "iProc ERROR: " line)
#f)
)
)
)
(lambda () (close-input-port proc-err)))))
)
(let
((error (string-append "iProc ERROR: Command '" command "' could
not be executed!")))
(if editor
(send editor insert error)
(sx-alert #f "iProc ERROR" (string-append "iProc ERROR: " error)
#f)
)
)
) ; end of if running
)
(thread-wait thd)
(sleep 0.5)
)
)
)
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