I've problem with my file handling program. See this

[Walter Roberson]

I have a problem reading the float values.
I modiifed my above code as:
....
fclose(fp);
fp=NULL;
fp = fopen("stuff", "r") ;
for( i=0; i<=5; i++)
{
fscanf( fp, "%d:%[^:]s:%.2[^:]f\n" , &i, &str, &f);
printf("Hi %s %d %.2f Size:%d\n", str, i, f, strlen(str));
}

Can i Use [^:] to limit float values as above.
Now the output is:
Hi Hello 0 0.00 Size:5
Hi Hello 1 0.00 Size:5
Hi Hello 2 0.00 Size:5
Hi Hello 3 0.00 Size:5
Hi Hello 4 0.00 Size:5
Hi Hello 5 0.00 Size:5

Please tell me how to solve this new problem. Thanks in advance Walter.

You do not need to use %[^:] or anything similar to limit reading
in float values: the parser will stop as soon as it encounters any
character which is not allowed in a float.

But your problem is not exactly where you were expecting. Your
new difficulty is in your fscanf() format where you have %[:]s

This does NOT mean:
"skip leading whitespace, then read a string of characters
until end of file or the next whitespace or a ':' is reached,
leaving the whitespace or ':' in the buffer"

What it *does* mean is:
"do NOT skip any leading whitespace; read a string of
characters (including whitespace) until end of file or a
':' is reached, leaving the ':' in the buffer; then once
that is done, look for the literal character 's' in the
input".

But since your input does not have a literal character 's'
at that point (and cannot have, since you are either at EOF
or at a ':'), the rest of the fscanf() fails, leaving all the
rest of the values to be read unchanged.

To be more clear about this: %[^:] is a format specifier
all by itself, introduced by the '%' (as all format
specifiers are), and with its type being indicated by the '['.
The format specification extends until the next non-escaped ']'
and ends there. Anything after that point is not part of that
format specifier. [^:] is NOT a modifier of a %s format specifier:
it is a format specifier all of its own, with different rules
than %s. For example, %s skips whitespace but %[] does not.

 

[Dave Thompson]

<OT: news format>

The original posting contained sample output of the program. That
sample output included non-ASCII characters. <snip>
The posting also contained incidental encodings of all the equal
signs (because they introduce quoted-printable characters), and
as well an encoding of a period that happened to occur at the
beginning of a line.

I didn't notice that one, so I went back and looked. It wasn't even at
the beginning of a line, which would be silly enough. It was the
_second_ position on a line, after a dollarsign. My bemusement at
google's craziness soars to even greater heights than before. Maybe
they think the news spool will somehow be used as perl scripts?

- David.Thompson1 at worldnet.att.net