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+--- Thread: scanf character (/Thread-scanf-character)
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RE: scanf character - chemicalrage - 12-25-2012
whenever you declare a char data type, use %c or %s as the format specifier.
int - %d
long int - %ld
float - %f which I believe you already know
char - %s / %c
RE: scanf character - Deque - 12-26-2012
(12-20-2012, 06:31 PM)Xe.4 Wrote: Thanks, that solved the problem. but I want to know the reason aswell .
There is still a newline in the buffer which is read into op as character. Flushing the buffer will help. Using a space in scanf triggers it to scan for whitespaces in order to ignore them. You can see this in the reference and the usage of the format parameter: http://www.cplusplus.com/reference/cstdio/scanf/
Quote:Whitespace character: the function will read and ignore any whitespace characters encountered before the next non-whitespace character (whitespace characters include spaces, newline and tab characters -- see isspace). A single whitespace in the format string validates any quantity of whitespace characters extracted from the stream (including none).
That means putting a space into the format paramter will make it ignore the newline in the buffer.
(12-23-2012, 04:15 PM)h4r0015k Wrote: i have read somewhere that getchar() are vulnerable and is recommended not to use it.
scanf is vulnerable too (format string attacks).
(12-25-2012, 11:25 PM)chemicalrage Wrote: whenever you declare a char data type, use %c or %s as the format specifier.
int - %d
long int - %ld
float - %f which I believe you already know
char - %s / %c
Your answer has nothing to do with the problem or the question.
RE: scanf character - Xe.4 - 12-26-2012
Thanks everyone for having opinions.
RE: scanf character - chipp - 12-30-2012
(12-21-2012, 06:28 AM)H4R0015K Wrote: %c format specifier requires a blank space before it because it start from a blank space or whitespace it does not store the blank space if it is not there it will skip the scanf fuction to solve this you can use %s which is string format specifier or leave a blank space before %c.
i just did know this, do you have an explanation links?
RE: scanf character - Deque - 12-30-2012
(12-30-2012, 07:52 PM)chipp Wrote:(12-21-2012, 06:28 AM)H4R0015K Wrote: %c format specifier requires a blank space before it because it start from a blank space or whitespace it does not store the blank space if it is not there it will skip the scanf fuction to solve this you can use %s which is string format specifier or leave a blank space before %c.
i just did know this, do you have an explanation links?
I gave one in my post.