It certainly is showing error but you're not looking for it. That's what scanf()'s return value is for, it returns 0 if it reads no values, 1 if it found 1 value, 2 for 2, etc. Each %... code counts as one "value".
The buffering thing is a known issue with scanf(). It's a "feature" -- it stops scanning at the first bad character -- which is pretty useless if you're not building a compiler.
fflush should work, if you tell it which stream to flush, which you are not. But the proper way to avoid these buffer problems is to not use scanf().
You can still use sscanf though, which is just as good without the problems! It scans a string, and has no buffer to leave things in.
Here's the usual way to do it:
Last edited by Corona688; 08-08-2014 at 12:18 PM..
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Discussion started by: fozilla
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LEARN ABOUT PHP
total
TOTAL(1) General Commands Manual TOTAL(1)NAME
total - sum up columns
SYNOPSIS
total [ -m ][ -sE | -p | -u | -l ][ -i{f|d}[N] ][ -o{f|d} ][ -tC ][ -N [ -r ]] [ file .. ]
DESCRIPTION
Total sums up columns of real numbers from one or more files and prints out the result on its standard output.
By default, total computes the straigt sum of each input column, but multiplication can be specified instead with the -p option. Likewise,
the -u option means find the upper limit (maximum), and -l means find the lower limit (minimum).
Sums of powers can be computed by giving an exponent with the -s option. (Note that there is no space between the -s and the exponent.)
This exponent can be any real number, positive or negative. The absolute value of the input is always taken before the power is computed
in order to avoid complex results. Thus, -s1 will produce a sum of absolute values. The default power (zero) is interpreted as a straight
sum without taking absolute values.
The -m option can be used to compute the mean rather than the total. For sums, the arithmetic mean is computed. For products, the geomet-
ric mean is computed. (A logarithmic sum of absolute values is used to avoid overflow, and zero values are silently ignored.)
If the input data is binary, the -id or -if option may be given for 64-bit double or 32-bit float values, respectively. Either option may
be followed immediately by an optional count, which defaults to 1, indicating the number of double or float binary values to read per
record on the input file. (There can be no space between the option and this count.) Similarly, the -od and -of options specify binary
double or float output, respectively. These options do not need a count, as this will be determined by the number of input channels.
A count can be given as the number of lines to read before computing a result. Normally, total reads each file to its end before producing
its result, but this behavior may be overridden by inserting blank lines in the input. For each blank input line, total produces a result
as if the end-of-file had been reached. If two blank lines immediately follow each other, total closes the file and proceeds to the next
one (after reporting the result). The -N option (where N is a decimal integer) tells total to produce a result and reset the calculation
after every N input lines. In addition, the -r option can be specified to override reinitialization and thus give a running total every N
lines (or every blank line). If the end of file is reached, the current total is printed and the calculation is reset before the next file
(with or without the -r option).
The -tC option can be used to specify the input and output tab character. The default tab character is TAB.
If no files are given, the standard input is read.
EXAMPLE
To compute the RMS value of colon-separated columns in a file:
total -t: -m -s2 input
To produce a running product of values from a file:
total -p -1 -r input
BUGS
If the input files have varying numbers of columns, mean values will certainly be off. Total will ignore missing column entries if the tab
separator is a non-white character, but cannot tell where a missing column should have been if the tab character is white.
AUTHOR
Greg Ward
SEE ALSO cnt(1), neaten(1), rcalc(1), rlam(1), tabfunc(1)RADIANCE 2/3/95 TOTAL(1)