Question about C?

[Pravin Shetty]

Hi to all,

Q)
main()
{
int c;
c=getchar();

while(c!=EOF)
{
putchar(c);
c=getchar();
}
}

: - why instead of declaring c as a char is declaered as an int?
why EOF is defined as an int in <stdio.h>

 

[SnaiL]

Good day, dear colleague and merry xmas ;-)

Please read manual --- http://bama.ua.edu/cgi-bin/man-cgi?getchar+3C
Good luck!

 

[Mike Wahler]

Hi to all,

Q)
main()
{
int c;
c=getchar();

while(c!=EOF)
{
putchar(c);
c=getchar();
}
}

: - why instead of declaring c as a char is declaered as an int?

Because 'getchar()' returns type 'int'.

why EOF is defined as an int in <stdio.h>

So that it can be distinguished from any possible 'char' value.

-Mike

 

[Ben Pfaff]

Hi to all,

Q)
main()
{
int c;
c=getchar();

while(c!=EOF)
{
putchar(c);
c=getchar();
}
}

: - why instead of declaring c as a char is declaered as an int?

It's in the FAQ.

12.1: What's wrong with this code?

char c;
while((c = getchar()) != EOF) ...

A: For one thing, the variable to hold getchar's return value must
be an int. getchar() can return all possible character values,
as well as EOF. By squeezing getchar's return value into a
char, either a normal character might be misinterpreted as EOF,
or the EOF might be altered (particularly if type char is
unsigned) and so never seen.

References: K&R1 Sec. 1.5 p. 14; K&R2 Sec. 1.5.1 p. 16; ISO
Sec. 6.1.2.5, Sec. 7.9.1, Sec. 7.9.7.5; H&S Sec. 5.1.3 p. 116,
Sec. 15.1, Sec. 15.6; CT&P Sec. 5.1 p. 70; PCS Sec. 11 p. 157.

why EOF is defined as an int in <stdio.h>

I think it follows from the above.

 

[Keith Thompson]

Q)
main()
{
int c;
c=getchar();

while(c!=EOF)
{
putchar(c);
c=getchar();
}
}

: - why instead of declaring c as a char is declaered as an int?
why EOF is defined as an int in <stdio.h>

The C FAQ is at <http://www.eskimo.com/~scs/C-faq/top.html>.
See question 12.1.