sscanf parseing a datestring

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Sat, 2014-11-29 20:44
#1
JosDuchIt
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sscanf parseing a datestring

sscanf(datestr, "%[^-]-%[^-]-%[^;];",yr ,mont ,day );
returns for the datestring 2009-03-22
yr 200903
mont 03
day 22
what is wrong with the year?

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Sun, 2014-11-30 14:45
Massi
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@JosDuchIt Rewrite the

@JosDuchIt

Rewrite the format string (2nd parameter) as

"%[^'-']-%[^'-']-%[^';'];"

and check the return value

if ( sscanf() != 3 )
{
/* error */
}

assuming datestr, yr, mont, day declared and used correctly, not provided here.

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Sun, 2014-11-30 16:25
(Reply to #2)
JosDuchIt
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@Massi, thanks for the

@Massi,
thanks for the suggestion.

It does not work as expcted either though:

typical reasult of the code below

9.Stock:Dev/C_Snippets_Working> ram:parsedate
Please enter a datestring (separations with -).
1914-10-06;
You typed:
1914-10-06;

1914-10-06;

year 1914-10-06;
month -10-06;
day
year 1914-10-06;
month -10-06;
day

9.Stock:Backup_Datas/Gui4Cli/Dev/C_Snippets_Working> ram:parsedate
Please enter a datestring (separations with -).
1914-10-06;
You typed:
1914-10-06;

1914-10-06;

year 1914-10-06;
month -10-06;
day
year 1914-10-06;
month -10-06;
day 

  1. #include <stdio.h>  //puts , sscanf
  2. #include <string.h>//
  3.  
  4. #define BUFFERSIZE 30
  5. int main() {
  6.  
  7.   char* bytes_read;
  8.   char datestr[BUFFERSIZE];
  9.   char yr[4], mont[9], day[9];
  10.   char *year;
  11.   char *month;
  12.   char *thisday;
  13.   puts ("Please enter a datestring  (separations with -).");
  14.   bytes_read = fgets (datestr, BUFFERSIZE, stdin); 
  15.   if (!(bytes_read))
  16.     {
  17.       puts ("ERROR!");
  18.     }
  19.   else
  20.     {
  21. 	puts ("You typed:");
  22. 	puts (datestr);
  23. 	puts (bytes_read);
  24. 	//sscanf(datestr, " %[^-]-%[^-]-%[^;];",&yr ,&mont ,&day );
  25. 	sscanf(datestr, " %[^'-']-%[^'-']-%[^';'];",&yr ,&mont ,&day ); 
  26.  
  27. 	year = yr;
  28. 	month = mont;
  29. 	thisday = day;
  30. 	printf("year %s month %s day %s\n", yr, mont, day); 
  31. 	printf("year %s month %s day %s\n", year, month, thisday); 
  32.  
  33.     }
  34.   return 0;
  35. }
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Sun, 2014-11-30 19:28
(Reply to #3)
Massi
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@JosDuchIt You didn' t check

@JosDuchIt

You didn' t check the sscanf() return value, anyway.

Assuming your date format is YYYY-MM-DD;

1) yr should be declared as char yr[ 4 + 1 ], to be able to store the string termination character '\0' added by sscanf() itself (same for mont[ 2 + 1 ] and day[ 2 + 1 ])

2) if I remember well fgets() should read (BUFFERSIZE - 1) chars (see documentation)

3) change sscanf(datestr, " %[^'-']-%[^'-']-%[^';'];",&yr ,&mont ,&day ); with sscanf(datestr, " %[^'-']-%[^'-']-%[^';'];",yr ,mont ,day );

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Mon, 2014-12-01 10:33
(Reply to #4)
JosDuchIt
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@Massi Thanks the yr[4] was

@Massi

Thanks

the yr[4] was the main culprit

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