Date: Mon, 23 Apr 2001 10:34:27 -0700 From: "Jeremiah Gowdy" <jgowdy@home.com> To: <david@angra.uac.pt>, <questions@FreeBSD.ORG> Subject: Re: fgets/fputs Message-ID: <000701c0cc1b$a7c458a0$015778d8@sherline.net> References: <0104231717100C.05409@david>
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----- Original Message -----
From: "David" <david@angra.uac.pt>
To: <questions@FreeBSD.ORG>
Sent: Monday, April 23, 2001 10:08 AM
Subject: fgets/fputs
> I have a doubt on libc:
>
> Both fputs and fgets functions use a char* instead of char[255]
> fgets (char *s, int count, FILE *stream)
> fputs (const char *s, FILE *stream)
Dude, why would they use char[255] ? They're any size you allocate.
void main(void)
{
char str[255];
fgets(str,255,stdin);
fputs(str,stdout);
}
or
void main(void)
{
char *str;
str=malloc(255);
fgets(str,255,stdin);
fputs(str,stdout);
}
> but the program only works when I define char[255] instead of char* as I
show in
> the source code below:...Why?
char[255] allocates 255 bytes of data. char* is only a pointer, which
points to nothing until you allocate some memory for it to point to. Your
question is not really about libc. It's about a lack of basic understanding
of "strings" (or lack therof) and pointers in C. You need a C programming
book. The questions you're asking would be the first 3 chapters of any good
C book. Good luck :)
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