D - Stupid question
- Karl Bochert (29/29) Nov 30 2002 Pardon my stupidity, but
- Walter (13/42) Nov 30 2002 The following works:
- Karl Bochert (8/23) Nov 30 2002 Not for me.
- Karl Bochert (72/87) Nov 30 2002 In case it's relevant here's a few details.
- Walter (5/92) Nov 30 2002 Please post a complete program that fails, that makes it a lot easier fo...
- Karl Bochert (62/65) Nov 30 2002 I shrank the program to its minimum and, !remarkably!, the problem did N...
- Karl Bochert (63/66) Nov 30 2002 Just read my own post.
- Walter (6/71) Nov 30 2002 Thanks, I'll check it out. -Walter
- Karl Bochert (59/61) Dec 01 2002 One of my earlier posts (# 9635 -- 113 lines) -showed 8 different ways
- Walter (8/73) Nov 30 2002 The first thing I notice is the gc isn't being started up and shutdown i...
- anderson (4/98) Nov 30 2002 How come the gc can't be automaticly stated up in WinMain by the D compi...
-
Walter
(6/107)
Dec 01 2002
Because I haven't written the code to do that
. - Sean L. Palmer (7/14) Dec 01 2002 Why are you using WinMain anyway? There's nothing there that can't be
- Walter (9/41) Dec 01 2002 Will fail because you're pointing into the stack of a returned function.
Pardon my stupidity, but
char[] foo()
{
char[] x;
char[128] buf= "qwerty"
// How do I return "querty" ?!?
}
I have tried scores of things over the last 8 hours without success.
The best I have come up with is:
char[] foo()
{
char[128] buf = "qwerty"
char[] x ="aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
// enuf a's for max size of buf!
x.length = 6;
for (i = 0; i < 6; ++i) {
x[i] = buf [i];
}
return x;
}
All attempts at using
x[] =
or
buf.dup
or
new char[128]
have failed.
What am I missing.
Karl Bochert
Nov 30 2002
The following works:
char[] foo()
{
return "querty";
}
as does:
char[] foo()
{
char[128] buf= "qwerty";
return buf.dup;
}
"Karl Bochert" <kbochert copper.net> wrote in message
news:1103_1038645905 bose...
Pardon my stupidity, but
char[] foo()
{
char[] x;
char[128] buf= "qwerty"
// How do I return "querty" ?!?
}
I have tried scores of things over the last 8 hours without success.
The best I have come up with is:
char[] foo()
{
char[128] buf = "qwerty"
char[] x ="aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
// enuf a's for max size of buf!
x.length = 6;
for (i = 0; i < 6; ++i) {
x[i] = buf [i];
}
return x;
}
All attempts at using
x[] =
or
buf.dup
or
new char[128]
have failed.
What am I missing.
Karl Bochert
Nov 30 2002
Karl Bochert <kbochert copper.net>
On Sat, 30 Nov 2002 10:51:07 -0800, "Walter" <walter digitalmars.com> wrote:
The following works:
char[] foo()
{
return "querty";
}
as does:
char[] foo()
{
char[128] buf= "qwerty";
return buf.dup;
}
Not for me.
I get an 'invalid page fault' (Win98) when the program returns.
With some strings and techniques, I get som garbage data back.
After many, many attempts, it appears that nothing will convince
the dynamic array char[] in foo() to get larger.
??
Karl Bochert
Nov 30 2002
On Sat, 30 Nov 2002 10:51:07 -0800, "Walter" <walter digitalmars.com> wrote:
The following works:
char[] foo()
{
return "querty";
}
as does:
char[] foo()
{
char[128] buf= "qwerty";
return buf.dup;
}
In case it's relevant here's a few details.
WIN98 platform, DMC v8.31 and DMD downloaded 2 days ago.
The 'application' is a windows I/O module that uses stdio for file
output and Windows API for console I/O. I had a working version in C
and translated it to D. (quite easy).
The shell script:
DMD=C:\d\dmd\bin\dmd.exe
LIB=C:\d\dmd\lib;C:\d\dm\lib
#set LINKCMD=%DMD\dm\bin\link
DFLAGS=
$(DMD) -c winio $(DFLAGS)
$(DMD) winio.obj snn.lib -L/map win.def
WIN.DEF contains:
EXETYPE NT
SUBSYSTEM WINDOWS
The relevant code looks something like:
char[] foo() // With an assortment of things I have tried
{
char[] x;
char[128] buf = "qwerty";
// modify buf ok?
strcpy (buf, "A test");
// should all of these return the same thing?
// -- they all fail --
//1
x = buf[0..3];
return x;
//2
return buf[0..3];
//3
x = buf;
x.length = 4;
return x;
//4
x = "A te"
return x;
//5
x = buf;
return x[1..4];
//6
return "A te";
//7
x.length = 4;
buf[4] = 0;
strcpy (x, buf);
return x;
}
extern (Windows)
int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
LPSTR szCmdLine, int iCmdShow)
{
int argc;
char **argv;
char[] line;
OS_init (); // check for redirection -- setup STDIN, etc.
// show_console ();
Fputs (STDERR, "Hello from stderr!\n");
line = foo();
// while(1){};
Fprintf (STDERR, "%.*s!\n", "test");
Fprintf (STDERR, "XX%.*s", line);
Fprintf (STDERR, "STDIN= %d %d\n", STDIN, stdin);
Fprintf (STDERR, "STDOUT= %d %d\n", STDOUT, stdout);
Fprintf (STDERR, "STDERR= %d %d\n", STDERR, stderr);
Fprintf (STDERR, "STDKEY= %d\n", STDKEY);
...
Without the call to foo() it runs fine.
With foo(), it causes a memory protection fault, even with the
infinite loop.
Karl Bochert
Nov 30 2002
Please post a complete program that fails, that makes it a lot easier for us. "Karl Bochert" <kbochert copper.net> wrote in message news:1104_1038693845 bose...On Sat, 30 Nov 2002 10:51:07 -0800, "Walter" <walter digitalmars.com>wrote:The following works: char[] foo() { return "querty"; } as does: char[] foo() { char[128] buf= "qwerty"; return buf.dup; }In case it's relevant here's a few details. WIN98 platform, DMC v8.31 and DMD downloaded 2 days ago. The 'application' is a windows I/O module that uses stdio for file output and Windows API for console I/O. I had a working version in C and translated it to D. (quite easy). The shell script: DMD=C:\d\dmd\bin\dmd.exe LIB=C:\d\dmd\lib;C:\d\dm\lib #set LINKCMD=%DMD\dm\bin\link DFLAGS= $(DMD) -c winio $(DFLAGS) $(DMD) winio.obj snn.lib -L/map win.def WIN.DEF contains: EXETYPE NT SUBSYSTEM WINDOWS The relevant code looks something like: char[] foo() // With an assortment of things I have tried { char[] x; char[128] buf = "qwerty"; // modify buf ok? strcpy (buf, "A test"); // should all of these return the same thing? // -- they all fail -- //1 x = buf[0..3]; return x; //2 return buf[0..3]; //3 x = buf; x.length = 4; return x; //4 x = "A te" return x; //5 x = buf; return x[1..4]; //6 return "A te"; //7 x.length = 4; buf[4] = 0; strcpy (x, buf); return x; } extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; char[] line; OS_init (); // check for redirection -- setup STDIN, etc. // show_console (); Fputs (STDERR, "Hello from stderr!\n"); line = foo(); // while(1){}; Fprintf (STDERR, "%.*s!\n", "test"); Fprintf (STDERR, "XX%.*s", line); Fprintf (STDERR, "STDIN= %d %d\n", STDIN, stdin); Fprintf (STDERR, "STDOUT= %d %d\n", STDOUT, stdout); Fprintf (STDERR, "STDERR= %d %d\n", STDERR, stderr); Fprintf (STDERR, "STDKEY= %d\n", STDKEY); ... Without the call to foo() it runs fine. With foo(), it causes a memory protection fault, even with the infinite loop. Karl Bochert
Nov 30 2002
On Sat, 30 Nov 2002 15:23:09 -0800, "Walter" <walter digitalmars.com> wrote:Please post a complete program that fails, that makes it a lot easier for us.I shrank the program to its minimum and, !remarkably!, the problem did NOT go away. Here it is. The windows part was tested in C. import windows; import c.stdio; import string; extern (Windows) { int AllocConsole (); }; HANDLE STDERR; static void show_console() { AllocConsole(); // Must AllocConsole beore getting standard handles!! STDERR = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_WRITE, (SECURITY_ATTRIBUTES*) 0,// Security not inherited 0, OPEN_EXISTING, (HANDLE)0); } char[] foo () { char[] x ; char[6] buf = "abcd"; // uint i; // x.length = 6; // for (i = 0; i < 6; ++i) { // x[i] = buf[i]; // } x = buf.dup; return x; } void Fputs(HANDLE fd, char[] out_string) { uint len; len = out_string.length; WriteFile(fd, // handle to file out_string, // data buffer len, // number of bytes to write &len, // number of bytes written (OVERLAPPED*) 0 // no overlapped buffer ); } //HINSTANCE winInstance; extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; show_console(); char[] line; Fputs (STDERR, "Hello"); line = foo(); // while(1) {}; Fputs (STDERR, "Hello"); while(1){}; // Hang the console open for reading return 0; }
Nov 30 2002
On Sat, 30 Nov 2002 15:23:09 -0800, "Walter" <walter digitalmars.com> wrote:Please post a complete program that fails, that makes it a lot easier for us.Just read my own post. Here's a version without the tabs. import windows; import c.stdio; import string; extern (Windows) { int AllocConsole (); }; HANDLE STDERR; static void show_console() /* set up a console window if not done yet */ { AllocConsole(); // Must AllocConsole beore getting standard handles!! STDERR = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_WRITE, (SECURITY_ATTRIBUTES*) 0,// Security not inherited 0, OPEN_EXISTING, (HANDLE)0); } char[] foo () { char[] x ; char[6] buf = "abcd"; // uint i; // x.length = 6; // for (i = 0; i < 6; ++i) { // x[i] = buf[i]; // } x = buf.dup; return x; } void Fputs(HANDLE fd, char[] out_string) { uint len; len = out_string.length; WriteFile(fd, // handle to file out_string, // data buffer len, // number of bytes to write &len, // number of bytes written (OVERLAPPED*) 0 // overlapped buffer ); } //HINSTANCE winInstance; extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; show_console(); char[] line; Fputs (STDERR, "Hello"); line = foo(); // while(1) {}; Fputs (STDERR, "Hello"); while(1){}; // Hang the console open return 0; }
Nov 30 2002
Thanks, I'll check it out. -Walter "Karl Bochert" <kbochert copper.net> wrote in message news:1103_1038703271 bose...On Sat, 30 Nov 2002 15:23:09 -0800, "Walter" <walter digitalmars.com>wrote:forPlease post a complete program that fails, that makes it a lot easierinheritedus.Just read my own post. Here's a version without the tabs. import windows; import c.stdio; import string; extern (Windows) { int AllocConsole (); }; HANDLE STDERR; static void show_console() /* set up a console window if not done yet */ { AllocConsole(); // Must AllocConsole beore getting standard handles!! STDERR = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_WRITE, (SECURITY_ATTRIBUTES*) 0,// Security not0, OPEN_EXISTING, (HANDLE)0); } char[] foo () { char[] x ; char[6] buf = "abcd"; // uint i; // x.length = 6; // for (i = 0; i < 6; ++i) { // x[i] = buf[i]; // } x = buf.dup; return x; } void Fputs(HANDLE fd, char[] out_string) { uint len; len = out_string.length; WriteFile(fd, // handle to file out_string, // data buffer len, // number of bytes to write &len, // number of bytes written (OVERLAPPED*) 0 // overlapped buffer ); } //HINSTANCE winInstance; extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; show_console(); char[] line; Fputs (STDERR, "Hello"); line = foo(); // while(1) {}; Fputs (STDERR, "Hello"); while(1){}; // Hang the console open return 0; }
Nov 30 2002
On Sat, 30 Nov 2002 20:47:27 -0800, "Walter" <walter digitalmars.com> wrote:Thanks, I'll check it out. -Walterof returning the char[]. Can you tell me which are supposed to work? A large portion of my problem is that I can't tell a bug from my mis-understanding. Here are a few further simplifications of the 'foo()' function in my previous example //calling this is ok void foo () { char[80] buf; } .. foo () // //calling this fails void foo () { char[80] buf = "abcd"; // init a [N] } //OK char[] x = "1234567890"; void foo () { char[80] buf = "abcd"; uint i; for (i = 0; i < 4; ++i) { buf[i] = 'x'; } x.length = 4; for (i = 0; i < 4; ++i) { x[i] = buf[i]; } } //fails char[] x; void foo () { char[80] buf; uint i; for (i = 0; i < 4; ++i) { buf[i] = 'x'; } x.length = 4; // enlarge a [] for (i = 0; i < 4; ++i) { x[i] = buf[i]; } } //fails char[] x = "1234567890"; void foo () { char[80] buf = "abcd"; uint i; for (i = 0; i < 4; ++i) { buf[i] = 'x'; } x = buf.dup; // use dup }
Dec 01 2002
The first thing I notice is the gc isn't being started up and shutdown in WinMain(). Check out the example in www.digitalmars.com/index.html under "D for Win32" and "Windows Executables." "Karl Bochert" <kbochert copper.net> wrote in message news:1103_1038703271 bose...On Sat, 30 Nov 2002 15:23:09 -0800, "Walter" <walter digitalmars.com>wrote:forPlease post a complete program that fails, that makes it a lot easierinheritedus.Just read my own post. Here's a version without the tabs. import windows; import c.stdio; import string; extern (Windows) { int AllocConsole (); }; HANDLE STDERR; static void show_console() /* set up a console window if not done yet */ { AllocConsole(); // Must AllocConsole beore getting standard handles!! STDERR = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_WRITE, (SECURITY_ATTRIBUTES*) 0,// Security not0, OPEN_EXISTING, (HANDLE)0); } char[] foo () { char[] x ; char[6] buf = "abcd"; // uint i; // x.length = 6; // for (i = 0; i < 6; ++i) { // x[i] = buf[i]; // } x = buf.dup; return x; } void Fputs(HANDLE fd, char[] out_string) { uint len; len = out_string.length; WriteFile(fd, // handle to file out_string, // data buffer len, // number of bytes to write &len, // number of bytes written (OVERLAPPED*) 0 // overlapped buffer ); } //HINSTANCE winInstance; extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; show_console(); char[] line; Fputs (STDERR, "Hello"); line = foo(); // while(1) {}; Fputs (STDERR, "Hello"); while(1){}; // Hang the console open return 0; }
Nov 30 2002
How come the gc can't be automaticly stated up in WinMain by the D compiler? "Walter" <walter digitalmars.com> wrote in message news:asc945$bsk$2 digitaldaemon.com...The first thing I notice is the gc isn't being started up and shutdown in WinMain(). Check out the example in www.digitalmars.com/index.html under"Dfor Win32" and "Windows Executables." "Karl Bochert" <kbochert copper.net> wrote in message news:1103_1038703271 bose...On Sat, 30 Nov 2002 15:23:09 -0800, "Walter" <walter digitalmars.com>wrote:forPlease post a complete program that fails, that makes it a lot easierinheritedus.Just read my own post. Here's a version without the tabs. import windows; import c.stdio; import string; extern (Windows) { int AllocConsole (); }; HANDLE STDERR; static void show_console() /* set up a console window if not done yet */ { AllocConsole(); // Must AllocConsole beore getting standard handles!! STDERR = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_WRITE, (SECURITY_ATTRIBUTES*) 0,// Security not0, OPEN_EXISTING, (HANDLE)0); } char[] foo () { char[] x ; char[6] buf = "abcd"; // uint i; // x.length = 6; // for (i = 0; i < 6; ++i) { // x[i] = buf[i]; // } x = buf.dup; return x; } void Fputs(HANDLE fd, char[] out_string) { uint len; len = out_string.length; WriteFile(fd, // handle to file out_string, // data buffer len, // number of bytes to write &len, // number of bytes written (OVERLAPPED*) 0 // overlapped buffer ); } //HINSTANCE winInstance; extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; show_console(); char[] line; Fputs (STDERR, "Hello"); line = foo(); // while(1) {}; Fputs (STDERR, "Hello"); while(1){}; // Hang the console open return 0; }
Nov 30 2002
Because I haven't written the code to do that <g>. "anderson" <anderson firestar.com.au> wrote in message news:asca6p$dn0$1 digitaldaemon.com...How come the gc can't be automaticly stated up in WinMain by the Dcompiler?"Walter" <walter digitalmars.com> wrote in message news:asc945$bsk$2 digitaldaemon.com...inThe first thing I notice is the gc isn't being started up and shutdowneasierWinMain(). Check out the example in www.digitalmars.com/index.html under"Dfor Win32" and "Windows Executables." "Karl Bochert" <kbochert copper.net> wrote in message news:1103_1038703271 bose...On Sat, 30 Nov 2002 15:23:09 -0800, "Walter" <walter digitalmars.com>wrote:Please post a complete program that fails, that makes it a lotforinheritedus.Just read my own post. Here's a version without the tabs. import windows; import c.stdio; import string; extern (Windows) { int AllocConsole (); }; HANDLE STDERR; static void show_console() /* set up a console window if not done yet */ { AllocConsole(); // Must AllocConsole beore getting standard handles!! STDERR = CreateFileA("CONOUT$", GENERIC_READ | GENERIC_WRITE, FILE_SHARE_WRITE, (SECURITY_ATTRIBUTES*) 0,// Security not0, OPEN_EXISTING, (HANDLE)0); } char[] foo () { char[] x ; char[6] buf = "abcd"; // uint i; // x.length = 6; // for (i = 0; i < 6; ++i) { // x[i] = buf[i]; // } x = buf.dup; return x; } void Fputs(HANDLE fd, char[] out_string) { uint len; len = out_string.length; WriteFile(fd, // handle to file out_string, // data buffer len, // number of bytes to write &len, // number of bytes written (OVERLAPPED*) 0 // overlapped buffer ); } //HINSTANCE winInstance; extern (Windows) int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR szCmdLine, int iCmdShow) { int argc; char **argv; show_console(); char[] line; Fputs (STDERR, "Hello"); line = foo(); // while(1) {}; Fputs (STDERR, "Hello"); while(1){}; // Hang the console open return 0; }
Dec 01 2002
Why are you using WinMain anyway? There's nothing there that can't be gotten later by other means. (GetModuleHandle etc.) Just use main(). Sean "anderson" <anderson firestar.com.au> wrote in message news:asca6p$dn0$1 digitaldaemon.com...How come the gc can't be automaticly stated up in WinMain by the Dcompiler?"Walter" <walter digitalmars.com> wrote in message news:asc945$bsk$2 digitaldaemon.com...inThe first thing I notice is the gc isn't being started up and shutdownWinMain(). Check out the example in www.digitalmars.com/index.html under"Dfor Win32" and "Windows Executables."
Dec 01 2002
"Karl Bochert" <kbochert copper.net> wrote in message news:1104_1038693845 bose...The relevant code looks something like: char[] foo() // With an assortment of things I have tried { char[] x; char[128] buf = "qwerty"; // modify buf ok? strcpy (buf, "A test"); // should all of these return the same thing? // -- they all fail -- //1 x = buf[0..3]; return x;Will fail because you're pointing into the stack of a returned function.//2 return buf[0..3];Will fail because you're pointing into the stack of a returned function.//3 x = buf; x.length = 4; return x;Will fail because you're pointing into the stack of a returned function.//4 x = "A te" return x;Will work - pointing into static data.//5 x = buf; return x[1..4];Will fail because you're pointing into the stack of a returned function.//6 return "A te";Will work, pointing into static data.//7 x.length = 4; buf[4] = 0; strcpy (x, buf); return x; }Will work, x points into heap.
Dec 01 2002