[brainy_creature]

why is ctype.h used as a header file?

[skyhawk133]

... because it's a header file...

[brainy_creature]

skyhawk133, on 14 Aug, 2006 - 11:03 AM, said:

... because it's a header file...

no.... i mean to ask what is it's utility????????
what can i implement if i use that header file?
like if i use math.h i can perform mathematical operations... which is impossible otherwise..

[Amadeus]

http://www-ccs.ucsd.edu/c/ctype.html

It should also be noted that the ctype.h library has been deprecated, and #include<cctype> should be used instead in C++

http://www.cs.bsu.ed...ders/cctype.htm

[born2c0de]

ctype (or cctype now) contains functions and MACRO's relating to a character's type.

For instance, case conversion functions are present in this header file and inclusion of this header file is required when you use the toupper() and tolower() functions.

You can even open the ctype.h in your Text Editor and have a look at all the functions and MACROs available.

[brainy_creature]

born2c0de, on 14 Aug, 2006 - 11:00 PM, said:

ctype (or cctype now) contains functions and MACRO's relating to a character's type.

For instance, case conversion functions are present in this header file and inclusion of this header file is required when you use the toupper() and tolower() functions.

You can even open the ctype.h in your Text Editor and have a look at all the functions and MACROs available.

oh ya.... i have encountered this toupper() function,
the goes like this-

 char ch,str[80];
for(;;)
{
do
{
printf("(E)nter grades \n");
printf("(R)eport grades \n");
gets(str);
ch=toupper(*str);
}
while(ch!='E'&& ch!='R' && ch!='Q');
switch(ch)
{
...

can you please explain what does toupper() and tolower() functions do... and how is toupper(*str) working here..?

[Amadeus]

toupper changes a character from lower case to upper case (by changing the related ASCII values). The code you've posted is calling the toupper() function with a character pointer as the paramter. you can read about the toupper function here:
http://www.opengroup...ns/toupper.html