getc Vs getchar Vs Scanf for reading a character from stdin
Of the below three functions:
getc getchar & scanf
which is the best one for reading a character from stdin and why?
Are there any known disadvantages or limitations for any of these functions whi开发者_Python百科ch makes one better than the other?
If you simply want to read a single character from stdin, then getchar()
is the appropriate choice. If you have more complicated requirements, then getchar()
won't be sufficient.
getc()
allows you to read from a different stream (say, one opened withfopen()
);scanf()
allows you to read more than just a single character at a time.
The most common error when using getchar()
is to try and use a char
variable to store the result. You need to use an int
variable, since the range of values getchar()
returns is "a value in the range of unsigned char
, plus the single negative value EOF
". A char
variable doesn't have sufficient range for this, which can mean that you can confuse a completely valid character return with EOF
. The same applies to getc()
.
from Beej's Guide to C Programming
All of these functions in one way or another, read a single character from the console or from a FILE. The differences are fairly minor, and here are the descriptions:
getc() returns a character from the specified FILE. From a usage standpoint, it's equivalent to the same fgetc() call, and fgetc() is a little more common to see. Only the implementation of the two functions differs.
fgetc() returns a character from the specified FILE. From a usage standpoint, it's equivalent to the same getc() call, except that fgetc() is a little more common to see. Only the implementation of the two functions differs.
Yes, I cheated and used cut-n-paste to do that last paragraph.
getchar() returns a character from stdin. In fact, it's the same as calling getc(stdin).
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