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Re: question about scanf

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On 04/16/2014 03:06 PM, TP wrote:
> Hi everybody,
> 
> I want to scan a string for an integer, but I don't want any other character 
> in the string after the integer, otherwise an error has to be raised.
> 
> I have scrutinized the manual page of scanf, the best solution I have found 
> is something as:
> 
> //////////////////
> #include <stdio.h>
> 
> int main( void )
> {
>     int occurrence;
>     int nbcharreadjustafteroccurrence;
>     int nbcharreadatendofthestring;
> 
>     printf("assignement number=%i\n"
>             , sscanf( "foo 3bar", "foo %d%n%*s%n"
>                 , &occurrence
>                 , &nbcharreadjustafteroccurrence
>                 , &nbcharreadatendofthestring ) );
> 
>     printf("characters after assignment=%i\n"
>             , nbcharreadatendofthestring - nbcharreadjustafteroccurrence );
> 
>     return 0;
> }
> 
> //////////////////
> 
> $ ./a.out 
> assignement number=1
> characters after assignment=3
> $
> 
> So I can raise an error if the number of characters is greater than zero.
> Is there any better solution?

"raise an error" is not very clear, and your example program doesn't
clarify it. I'll just print a message "Error raised", and you can insert
the appropriate code in place of that message:

include <stdio.h>
#include <string.h>

int main( void )
{
    int occurrence;
    int nbcharreadjustafteroccurrence;
    char string[] = "foo 3bar";

    printf("assignment number=%i\n"
            , sscanf(string, "foo %d%n"
                , &occurrence
                , &nbcharreadjustafteroccurrence));

    if(string[nbcharreadjustafteroccurrence])
    {
       printf("Error raised\n");
    }

    printf("characters after assignment=%zu\n"
            , strlen(string+nbcharreadjustafteroccurrence));

    return 0;
}

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question about scanf TP <TP@frenoespam.fr.invalid> - 2014-04-16 21:06 +0200
  Re: question about scanf Kaz Kylheku <kaz@kylheku.com> - 2014-04-16 21:38 +0000
  Re: question about scanf Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-04-16 22:59 +0100
    Re: question about scanf TP <TP@frenoespam.fr.invalid> - 2014-04-21 08:01 +0200
  Re: question about scanf James Kuyper <jameskuyper@verizon.net> - 2014-04-16 18:15 -0400
  Re: question about scanf "Bill Cunningham" <nospam@nspam.invalid> - 2014-04-20 09:47 -0400
  Re: question about scanf viju.kantah@gmail.com - 2014-04-20 07:04 -0700
    Re: question about scanf gazelle@shell.xmission.com (Kenny McCormack) - 2014-04-20 15:24 +0000
    Re: question about scanf "BartC" <bc@freeuk.com> - 2014-04-20 17:10 +0100

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