On Thu, 22 Feb 2001, Tony Lambiris wrote:
> when I set a pointer to the structure, and say, get the OS version:
>
> struct utsname *host_uname;
Are you allocating a memory buffer and pointing host_uname to it before
invoking uname:
struct utsname buf;
uname(&buf);
> os_version = malloc(strlen(host_uname->release));
You do not declare os_version in the code sample you give. I will assume
you mean:
char * os_version;
If you intend to copy the string pointed to by host_uname->release, then you
need to malloc one extra byte for the terminating NUL byte:
os_version = malloc( strlen(buf->release) + 1 );
> os_version = (host_uname->release);
Be aware that this does *NOT* copy the string pointed to by
host_uname->release to the buffer pointed to by os_version. Instead, it
copies the *pointer* contained in host_uname to os_version (which, hopefully,
is also a pointer). This is fine, but it means that if you destroy
host_uname, os_version will no longer be valid.
If you intended to copy the string, you need to use:
strcpy (os_version, host_uname->release);
But you should really use:
strncpy (os_version, host_uname->release, SIZE_OF_OS_VERSION_BUFFER);
That will prevent buffer overflow bugs.
> or perhaps I just suck at coding??
I would not go that far, but it is apparent you do not fully understand
string handling in C. That is pretty common; C string handling is notoriously
hard to master for new users, especially those used to other languages with a
built-in "string" type. I recommend _The C Programming Language_, Second
Edition, by Kernighan and Ritchie. Actually, I recommend two copies: One to
use, and one to place in a shrine. ;-)
--
Ben Scott <[EMAIL PROTECTED]>
Net Technologies, Inc. <http://www.ntisys.com>
Voice: (800)905-3049 x18 Fax: (978)499-7839
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