Infinite Loop

cdonlan · 11-30-2004, 04:08 PM

Hey guys im getting an Infinite Loop and i cannot figure out the problem here is how the code goes.

Code:

int endflag=0;
int choice;


while( endflag ==0)
{
     printf("enter choice\n");
     scanf("%d", choice);

     switch(choice)
     {
          case 1: /* function call */
                        break;

           case 2: /* another function call */
                       break;

           case 3: printf(".....")
                       endflag =1;
                       break;
           
          default: printf("please enter anouther choice")
                        break;
      }
}

It wont stop printf enter choice: please enter anouther choice.

Any ideas,
Chris

edit! sorry it was set as zero. Its fine until the default case.

**Dave_Sinkula** · 11-30-2004, 04:13 PM

Ah, scanf bites another. Look in the FAQ for ways to obtain numbers.

FAQ > How do I... (Level 1) > How do I get a number from the user (C)

bithub · 11-30-2004, 04:13 PM

well with the code you posted, execution never enters the while loop.

Edit: poster changed his code so that it enters loop

cdonlan · 11-30-2004, 06:15 PM

Mybad it should of been 0.

Still not working.

thanks

quzah · 11-30-2004, 06:39 PM

That's because you're not using scanf right. scanf requires you pass it pointers as its arguments. You aren't. If you had actually paid attention to your compiler's warnings...

Quote:

warning: format argument is not a pointer (arg2)

Try passing the address of the variable instead of the value.

Quzah.

cdonlan · 11-30-2004, 06:41 PM

No warning was given.

Thanks

quzah · 11-30-2004, 07:19 PM

Turn them on then. Because your life will be a whole lot easier if you use them.

Quzah.

VOX · 11-30-2004, 07:26 PM

Maybe he isn't using your compiler, hmm? I don't get that warning.

prog-bman · 11-30-2004, 07:33 PM

[edit]
try -Wall as a compiler switch
[/edit]

cdonlan · 11-30-2004, 07:40 PM

The warnings are on......

**Thantos** · 11-30-2004, 07:42 PM

Then get a better compiler that will warn you of such mistakes.

cdonlan · 11-30-2004, 07:57 PM

Thanks...lots of help

**Thantos** · 11-30-2004, 08:00 PM

Think about it this way: If you have a saw, that is old, rusted, and is missing half of it's teeth you'd buy a new saw. The compiler is the same way. If its not warning you of simple mistakes as type mismatch for scanf() and printf() then its missing some teeth and needs to be replaced.

So yes my post is helpful.

cdonlan · 11-30-2004, 08:05 PM

I understand the complier im using is not the best, and a little out dated. Regardless it is the one required by my professor.

So back to the question at hand....

Should i not use scanf or should i use some type of point to the switch.

Chris

**Thantos** · 11-30-2004, 08:08 PM

Use the address of operator (&) before the variable to pass a point to scanf

Code:

scanf("%d", &choice);

Can we get the name, email, and phone number of your professor so we may call and yell at him for using bad compilers?

11-30-2004, 04:08 PM	#1
cdonlan Registered User Join Date: Sep 2004 Posts: 49	Infinite Loop Hey guys im getting an Infinite Loop and i cannot figure out the problem here is how the code goes. Code: int endflag=0; int choice; while( endflag ==0) { printf("enter choice\n"); scanf("%d", choice); switch(choice) { case 1: /* function call / break; case 2: / another function call / break; case 3: printf(".....") endflag =1; break; default: printf("please enter anouther choice") break; } } It wont stop printf enter choice: please enter anouther choice. Any ideas, Chris edit! sorry it was set as zero. Its fine until the default case. Last edited by cdonlan; 11-30-2004 at 06:15 PM.*
cdonlan is offline

11-30-2004, 04:13 PM	#2
Dave_Sinkula Just Lurking Join Date: Oct 2002 Posts: 5,006	Ah, scanf bites another. Look in the FAQ for ways to obtain numbers. FAQ > How do I... (Level 1) > How do I get a number from the user (C) __________________ 7. It is easier to write an incorrect program than understand a correct one. 40. There are two ways to write error-free programs; only the third one works.* Last edited by Dave_Sinkula; 11-30-2004 at 04:41 PM. Reason: Added link for any FAQ-impaired visitors.
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11-30-2004, 04:13 PM	#3
bithub Registered User Join Date: Sep 2004 Location: California Posts: 3,029	well with the code you posted, execution never enters the while loop. Edit: poster changed his code so that it enters loop Last edited by bithub; 11-30-2004 at 04:17 PM.
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11-30-2004, 06:15 PM	#4
cdonlan Registered User Join Date: Sep 2004 Posts: 49	Mybad it should of been 0. Still not working. thanks
cdonlan is offline

11-30-2004, 06:41 PM	#6
cdonlan Registered User Join Date: Sep 2004 Posts: 49	No warning was given. Thanks
cdonlan is offline

11-30-2004, 07:19 PM	#7
quzah +++ OK NO CARRIER Join Date: Oct 2001 Posts: 11,292	Turn them on then. Because your life will be a whole lot easier if you use them. Quzah. __________________ Hundreds of thousands of dipshits can't be wrong. Are you up for the suck?
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11-30-2004, 07:26 PM	#8
VOX Deleting... Join Date: Oct 2004 Location: VA Posts: 94	Maybe he isn't using your compiler, hmm? I don't get that warning.
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11-30-2004, 07:33 PM	#9
prog-bman Sweet Join Date: Aug 2002 Location: Tucson, Arizona Posts: 1,758	[edit] try -Wall as a compiler switch [/edit] __________________ Woop? Last edited by prog-bman; 11-30-2004 at 07:38 PM.
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11-30-2004, 07:40 PM	#10
cdonlan Registered User Join Date: Sep 2004 Posts: 49	The warnings are on......
cdonlan is offline

11-30-2004, 07:42 PM	#11
Thantos & the hat of GPL slaying Join Date: Sep 2001 Posts: 5,732	Then get a better compiler that will warn you of such mistakes.
Thantos is offline

11-30-2004, 07:57 PM	#12
cdonlan Registered User Join Date: Sep 2004 Posts: 49	Thanks...lots of help
cdonlan is offline

11-30-2004, 08:00 PM	#13
Thantos & the hat of GPL slaying Join Date: Sep 2001 Posts: 5,732	Think about it this way: If you have a saw, that is old, rusted, and is missing half of it's teeth you'd buy a new saw. The compiler is the same way. If its not warning you of simple mistakes as type mismatch for scanf() and printf() then its missing some teeth and needs to be replaced. So yes my post is helpful.
Thantos is offline

11-30-2004, 08:05 PM	#14
cdonlan Registered User Join Date: Sep 2004 Posts: 49	I understand the complier im using is not the best, and a little out dated. Regardless it is the one required by my professor. So back to the question at hand.... Should i not use scanf or should i use some type of point to the switch. Chris
cdonlan is offline

11-30-2004, 08:08 PM	#15
Thantos & the hat of GPL slaying Join Date: Sep 2001 Posts: 5,732	Use the address of operator (&) before the variable to pass a point to scanf Code: scanf("%d", &choice); Can we get the name, email, and phone number of your professor so we may call and yell at him for using bad compilers?
Thantos is offline

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