fgets() and EOF

[twazzler]

Hello again,

Is there a way of turning my code below into a loop which terminates when the user types in "quit"? The usual methods don't seem to work - Pelles C keeps throwing errors about mystring being interpreted as an int? (It's clearly declared as a char array):

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define MAX 100

void reverse (char s[]);

int main (int argc, char *argv[]) 
{

      char mystring[MAX];

      printf("Please enter a string of characters.\nEnter quit when done.\n");
      
      fgets(mystring,MAX,stdin);

      reverse(mystring);


return 0;
}

void reverse (char mystring[])
{

	int x;
 x=strlen(mystring);

      for(x=strlen(mystring); x>=0; x--) 
		{
          printf("%c", mystring[x]);
		}
printf("\n");
}

[Bayint Naung]

Use strcmp(). Don't forget to fgets() will include '\n' char if there's one.
Post which line. and error message.

[CommonTater]

Hello again,

Is there a way of turning my code below into a loop which terminates when the user types in "quit"? The usual methods don't seem to work - Pelles C keeps throwing errors about mystring being interpreted as an int? (It's clearly declared as a char array):

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define MAX 100

void reverse (char s[]);

int main (int argc, char *argv[]) 
{

      char mystring[MAX];

      printf("Please enter a string of characters.\nEnter quit when done.\n");
      
      fgets(mystring,MAX,stdin);

      reverse(mystring);


return 0;
}

void reverse (char mystring[])
{

	int x;
 x=strlen(mystring);

      for(x=strlen(mystring); x>=0; x--) 
		{
          printf("%c", mystring[x]);
		}
printf("\n");
}

I just compiled and ran your code in Pelles C (v6.50 rc4) and it worked just fine.

The only change I'd make is to remove the x = strlen(mystring); above the for loop... but that's just housekeeping really.

For your quit when done thing...

do 
  {  
    //get user input as you are
  }  while (stricmp(mystring,"QUIT"));

should do the trick...

[twazzler]

Hi Tater,

Thanks for replying. Do you mean like this?

      char mystring[MAX];

      printf("Please enter a string of characters.\nEnter quit when done.\n");
      
        
	fgets(mystring,MAX,stdin);
	while (strcmp(mystring,"QUIT"));
	

      reverse(mystring);


return 0;
}

As now it just quits whatever is inputted

[CommonTater]

Hi Tater,

Thanks for replying. Do you mean like this?

No i did not mean like that.

Look what I wrote and what you wrote... see any resemblence whatsoever?

[twazzler]

You've lost me, sorry...

[Bayint Naung]

Check documentation of strcmp!!!
It returns zero if two strings are equal.

[CommonTater]

You've lost me, sorry...

Like this... with a minor revision for the newline from fgets...

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define MAX 100

void reverse (char s[]);

int main (int argc, char *argv[]) 
{

      char mystring[MAX];

    do
     {      
       printf("Please enter a string of characters.\nEnter quit when done.\n");
      
      fgets(mystring,MAX,stdin);

      reverse(mystring);
      } while (_stricmp(mystring,"QUIT\n"));

return 0;
}

void reverse (char mystring[])
{

	int x;
 x=strlen(mystring);

      for(x=strlen(mystring); x>=0; x--) 
		{
          printf("%c", mystring[x]);
		}
printf("\n");
}

Now... open the Pelles C help file click the index tab ... type in stricmp and press Enter.
Next put the flashing text cursor on the word stricmp and press F1 ...
Pelles C is probably the best documented compiler and library I've ever seen.

[Bayint Naung]

Don't forget that while strcmp() is standard function , stricmp or _stricmp is not.

[CommonTater]

Don't forget that while strcmp() is standard function , stricmp or _stricmp is not.

Of course... that's why I suggested he look it up in the help file... In Pelles C the help file very clearly identifies non-standard functions. If there's nothin in his task saying "Standard functions only" I don't see a problem using it.

The advantage of _strichr() in this situation is that it is not case sensitive so any permutation of quit, Quit QUIT, qUit, etc. will work.