1. Stumped by open("PRN","w")
- Posted by Jim <futures8 at EARTHLINK.NET>
Jan 21, 2001
-
Last edited Jan 22, 2001
The following code snippet is from a Windows program using Win32Lib.ew. If I run
it with exw.exe, on a machine with no
printer (or anything else) attached to the parallel port, it executes the
open("PRN","w") statement and assigns a valid
file handle (4), where I would have expected a -1. It also continues to the
puts(ThePrinter,line) and executes that.
In fact, under exw, the program runs to normal completion, when I would have
expected an abnormal termination.
The very same code, copied to an .ex file, and run under ex.exe executes in the
same way, but then crashes with a DOS
Critical Error when it hits the puts(ThePrinter,line) statement. In both
versions, I would have expected a -1 on the
open for the non-existent printer.
Can someone help me understand what I'm doing wrong here?
Thanks.
Totally perplexed.
Jim
------------------- <begin code >
object line
integer Patterns,ThePrinter,result
Patterns=open( "PATTERNS.TXT","rb" ) -- any text file of 80 or
more char.
if Patterns = -1 then
result = message_box( "Open Patterns.txt FAILED in
OnClick_ButtonPrint. Aborting. ","ERROR!", {} ) abort(1)
end if
ThePrinter = open("PRN","w")
if ThePrinter = -1 then
result = message_box( "Unable to find a printer; skipping.",
"ERROR!", {} ) -- never executed, although
no printer
else
while 1 do
line=gets(Patterns)
if atom(line) then
close(Patterns)
close(ThePrinter)
exit
end if
line=line[1..80]&"\n"
puts(ThePrinter,line) -- processed OK under exw.exw ;
crashes to DOS under ex.exe
end while
end if
---------< end code >
2. Re: Stumped by open("PRN","w")
- Posted by cEnsE <cense at MAIL.RU>
Jan 21, 2001
-
Last edited Jan 22, 2001
On Sun, 21 Jan 2001, Jim wrote:
>> The following code snippet is from a Windows program using Win32Lib.ew. If I
>> run it with exw.exe, on a machine with no
>> printer (or anything else) attached to the parallel port, it executes the
>> open("PRN","w") statement and assigns a valid
>> file handle (4), where I would have expected a -1. It also continues to the
>> puts(ThePrinter,line) and executes that.
>> In fact, under exw, the program runs to normal completion, when I would have
>> expected an abnormal termination.
>>
>> The very same code, copied to an .ex file, and run under ex.exe executes in
>> the same way, but then crashes with a DOS
>> Critical Error when it hits the puts(ThePrinter,line) statement. In both
>> versions, I would have expected a -1 on the
>> open for the non-existent printer.
>>
>> Can someone help me understand what I'm doing wrong here?
>>
>> Thanks.
>>
>> Totally perplexed.
>>
>> Jim
>>
>> ------------------- <begin code >
>> object line
>> integer Patterns,ThePrinter,result
>>
>> Patterns=open( "PATTERNS.TXT","rb" ) -- any text file of 80
>> or more char.
>> if Patterns = -1 then
>> result = message_box( "Open Patterns.txt FAILED in
>> OnClick_ButtonPrint. Aborting. ","ERROR!", {} ) abort(1)
>>
>> end if
>>
>> ThePrinter = open("PRN","w")
What exactly is this "PRN" ? the way you have it coded, if im not mistaken,
the open call will open a file in the current directory called PRN. I may
very well be mistaked but from a quick look over this "PRN" stands out as a
possible source of your problem.
>> if ThePrinter = -1 then
>> result = message_box( "Unable to find a printer; skipping.",
>> "ERROR!", {} ) -- never executed, although
>> no printer
>> else
>> while 1 do
>> line=gets(Patterns)
>> if atom(line) then
>> close(Patterns)
>> close(ThePrinter)
>> exit
>> end if
>> line=line[1..80]&"\n"
>> puts(ThePrinter,line) -- processed OK under exw.exw ;
>> crashes to DOS under ex.exe
>> end while
>> end if
>> ---------< end code >
I hope that helps, but if not, i tried.
--
evil, corruption and bad taste
^[cense]
3. Re: Stumped by open("PRN","w")
- Posted by Jim <futures8 at EARTHLINK.NET>
Jan 21, 2001
-
Last edited Jan 22, 2001
Hi,cEnsE,
Thanks for trying to help. But, this is one of those very rare instances in
which I think you may have missed the mark.
The code in question
ThePrinter = open("PRN","w")
has been pretty much copied directly from an example given in the Euphoria
documentation (see "open" in the docs).
The only difference being that I named the receiving variable differently, i.e.,
ThePrinter instead of Rob's file_num.
I did, however, try open("LPT1","w") and open("prn","w") and a few other
things before harrassing the list with my question.
As I said, thanks for taking the time to try to help.
Regards,
Jim
cEnsE wrote:
>
> What exactly is this "PRN" ? the way you have it coded, if im not mistaken,
> the open call will open a file in the current directory called PRN. I may
> very well be mistaked but from a quick look over this "PRN" stands out as a
> possible source of your problem.
>
> I hope that helps, but if not, i tried.
>
> --
> evil, corruption and bad taste
> ^[cense]
4. Re: Stumped by open("PRN","w")
- Posted by Dan B Moyer <DANMOYER at PRODIGY.NET>
Jan 21, 2001
-
Last edited Jan 22, 2001
cense,
>From the Euphoria refmanual, on "open",
<begin quote>
Some typical devices that you can open are:
"CON" - the console (screen)
"AUX" - the serial auxiliary port
"COM1" - serial port 1
"COM2" - serial port 2
"PRN" - the printer on the parallel port
"NUL" - a non-existent device that accepts and discards output
<end quote>
So, "PRN" is a device definition of the printer on the parallel port.
Dan Moyer
----- Original Message -----
From: "cEnsE" <cense at MAIL.RU>
To: <EUPHORIA at LISTSERV.MUOHIO.EDU>
Sent: Sunday, January 21, 2001 7:15 PM
Subject: Re: Stumped by open("PRN","w")
> On Sun, 21 Jan 2001, Jim wrote:
> >> The following code snippet is from a Windows program using Win32Lib.ew.
If I run it with exw.exe, on a machine with no
> >> printer (or anything else) attached to the parallel port, it executes
the open("PRN","w") statement and assigns a valid
> >> file handle (4), where I would have expected a -1. It also continues
to the puts(ThePrinter,line) and executes that.
> >> In fact, under exw, the program runs to normal completion, when I would
have expected an abnormal termination.
> >>
> >> The very same code, copied to an .ex file, and run under ex.exe
executes in the same way, but then crashes with a DOS
> >> Critical Error when it hits the puts(ThePrinter,line) statement. In
both versions, I would have expected a -1 on the
> >> open for the non-existent printer.
> >>
> >> Can someone help me understand what I'm doing wrong here?
> >>
> >> Thanks.
> >>
> >> Totally perplexed.
> >>
> >> Jim
> >>
> >> ------------------- <begin code >
> >> object line
> >> integer Patterns,ThePrinter,result
> >>
> >> Patterns=open( "PATTERNS.TXT","rb" ) -- any text file
of 80 or more char.
> >> if Patterns = -1 then
> >> result = message_box( "Open Patterns.txt FAILED in
OnClick_ButtonPrint. Aborting. ","ERROR!", {} ) abort(1)
> >>
> >> end if
> >>
> >> ThePrinter = open("PRN","w")
>
> What exactly is this "PRN" ? the way you have it coded, if im not
mistaken,
> the open call will open a file in the current directory called PRN. I may
> very well be mistaked but from a quick look over this "PRN" stands out as
a
> possible source of your problem.
>
>
> >> if ThePrinter = -1 then
> >> result = message_box( "Unable to find a printer;
skipping.", "ERROR!", {} ) -- never executed, although
> >> no printer
> >> else
> >> while 1 do
> >> line=gets(Patterns)
> >> if atom(line) then
> >> close(Patterns)
> >> close(ThePrinter)
> >> exit
> >> end if
> >> line=line[1..80]&"\n"
> >> puts(ThePrinter,line) -- processed OK under
exw.exw ; crashes to DOS under ex.exe
> >> end while
> >> end if
> >> ---------< end code >
>
> I hope that helps, but if not, i tried.
>
> --
> evil, corruption and bad taste
> ^[cense]
5. Re: Stumped by open("PRN","w")
On Sun, 21 Jan 2001, Dan B Moyer wrote:
>> cense,
>>
>> From the Euphoria refmanual, on "open",
>>
>> <begin quote>
>> Some typical devices that you can open are:
>>
>> "CON" - the console (screen)
>> "AUX" - the serial auxiliary port
>> "COM1" - serial port 1
>> "COM2" - serial port 2
>> "PRN" - the printer on the parallel port
>> "NUL" - a non-existent device that accepts and discards output
>>
>> <end quote>
>>
>> So, "PRN" is a device definition of the printer on the parallel port.
I was talking about the quotes, sorry, i was not specific enough
>> Dan Moyer
>>
>>
>> ----- Original Message -----
>> From: "cEnsE" <cense at MAIL.RU>
>> To: <EUPHORIA at LISTSERV.MUOHIO.EDU>
>> Sent: Sunday, January 21, 2001 7:15 PM
>> Subject: Re: Stumped by open("PRN","w")
>>
>>
>> > On Sun, 21 Jan 2001, Jim wrote:
>> > >> The following code snippet is from a Windows program using Win32Lib.ew.
>> If I run it with exw.exe, on a machine with no
>> > >> printer (or anything else) attached to the parallel port, it executes
>> the open("PRN","w") statement and assigns a valid
>> > >> file handle (4), where I would have expected a -1. It also continues
>> to the puts(ThePrinter,line) and executes that.
>> > >> In fact, under exw, the program runs to normal completion, when I would
>> have expected an abnormal termination.
>> > >>
>> > >> The very same code, copied to an .ex file, and run under ex.exe
>> executes in the same way, but then crashes with a DOS
>> > >> Critical Error when it hits the puts(ThePrinter,line) statement. In
>> both versions, I would have expected a -1 on the
>> > >> open for the non-existent printer.
>> > >>
>> > >> Can someone help me understand what I'm doing wrong here?
>> > >>
>> > >> Thanks.
>> > >>
>> > >> Totally perplexed.
>> > >>
>> > >> Jim
>> > >>
>> > >> ------------------- <begin code >
>> > >> object line
>> > >> integer Patterns,ThePrinter,result
>> > >>
>> > >> Patterns=open( "PATTERNS.TXT","rb" ) -- any text file
>> of 80 or more char.
>> > >> if Patterns = -1 then
>> > >> result = message_box( "Open Patterns.txt FAILED in
>> OnClick_ButtonPrint. Aborting. ","ERROR!", {} ) abort(1)
>> > >>
>> > >> end if
>> > >>
>> > >> ThePrinter = open("PRN","w")
>> >
>> > What exactly is this "PRN" ? the way you have it coded, if im not
>> mistaken,
>> > the open call will open a file in the current directory called PRN. I may
>> > very well be mistaked but from a quick look over this "PRN" stands out as
>> a
>> > possible source of your problem.
>> >
>> >
>> > >> if ThePrinter = -1 then
>> > >> result = message_box( "Unable to find a printer;
>> skipping.", "ERROR!", {} ) -- never executed, although
>> > >> no printer
>> > >> else
>> > >> while 1 do
>> > >> line=gets(Patterns)
>> > >> if atom(line) then
>> > >> close(Patterns)
>> > >> close(ThePrinter)
>> > >> exit
>> > >> end if
>> > >> line=line[1..80]&"\n"
>> > >> puts(ThePrinter,line) -- processed OK under
>> exw.exw ; crashes to DOS under ex.exe
>> > >> end while
>> > >> end if
>> > >> ---------< end code >
>> >
>> > I hope that helps, but if not, i tried.
>> >
>> > --
>> > evil, corruption and bad taste
>> > ^[cense]
--
evil, corruption and bad taste
^[cense]
6. Re: Stumped by open("PRN","w")
On Sun, 21 Jan 2001, Jim wrote:
>> Hi,cEnsE,
>>
>> Thanks for trying to help. But, this is one of those very rare instances in
>> which I think you may have missed the mark.
>>
>> The code in question
>>
>> ThePrinter = open("PRN","w")
>>
>> has been pretty much copied directly from an example given in the Euphoria
>> documentation (see "open" in the docs).
>>
>> The only difference being that I named the receiving variable differently,
>> i.e., ThePrinter instead of Rob's file_num.
>>
>> I did, however, try open("LPT1","w") and open("prn","w") and a few other
>> things before harrassing the list with my question.
>>
>> As I said, thanks for taking the time to try to help.
>>
>> Regards,
>>
>> Jim
Am I really stupid and do not understand "open( )"? should it read:
ThePrinter = open( PRN, "w" ) ? (note the no quotes). I think its just that
im stupid.
Is "PRN" a global variable or is it a special sequence? what if i wanted to
open a file called "PRN"?
>> cEnsE wrote:
>>
>> >
>> > What exactly is this "PRN" ? the way you have it coded, if im not mistaken,
>> > the open call will open a file in the current directory called PRN. I may
>> > very well be mistaked but from a quick look over this "PRN" stands out as a
>> > possible source of your problem.
>> >
>> > I hope that helps, but if not, i tried.
>> >
>> > --
>> > evil, corruption and bad taste
>> > ^[cense]
--
evil, corruption and bad taste
^[cense]
7. Re: Stumped by open("PRN","w")
Wow, i read the docs and now i understand. Sorry about all the confusion,
turns out im the one who needed help.
--
evil, corruption and bad taste
^[cense]
