11-28-2005
Ok simple question for simple knowledge...
Ok what is BSD exactly? I know its a type of open source but what is it exactly?
9 More Discussions You Might Find Interesting
1. UNIX for Advanced & Expert Users
Friends,
I did following exercise
$ echo '' > test
$ od -b test
$ echo "">test
$ od -b test
$echo > test
$od -b test
Every time I got the following output
0000000 012
0000001
But 012 is octal value for new line character .
Even though there is no apperent new line character... (6 Replies)
Discussion started by: j1yant
6 Replies
2. UNIX for Dummies Questions & Answers
Hi All,
I am new to UNIX Shell Scripting.
I want to know what is the difference between the following two statements.
if
and
if
Thanks & Regards (3 Replies)
Discussion started by: tvkamesh
3 Replies
3. UNIX for Dummies Questions & Answers
Can anyone tell me if there is a way to remove the encryption from Data CDs by UNIX? Or does anyone know of a program that can remove the encryption?
I would much appreciate it!
Thanks,
-Peaves (2 Replies)
Discussion started by: Peaves
2 Replies
4. Shell Programming and Scripting
Is it possible to establish an IF statement inside a case statement in a shell file ?
thx (2 Replies)
Discussion started by: TARFU
2 Replies
5. Programming
Hello. I'm a complete newbie to C programming. I have a C program that wasn't written by me where I need to write some wrappers around it to automate and make it easier for a client to use. The problem is that the program accepts standard input to control the program... I'm hoping to find a simple... (6 Replies)
Discussion started by: Xeed
6 Replies
6. Shell Programming and Scripting
i am doing ls -la
in the out put , first line is as
total 41621
What is this total? (2 Replies)
Discussion started by: Saurabh78
2 Replies
7. Shell Programming and Scripting
Hi,
Please don't berate me over the simplicity of these questions. I have recently gotten into bash shell scripting and enjoy it quite a bit. One thing I have not found the answer to though is when naming a shell script, what extension is normally used (ie myscript.?)? Also where is the standard... (5 Replies)
Discussion started by: msb65
5 Replies
8. Shell Programming and Scripting
Hello all!
This is my first post and I'm very new to programming. I would like help creating a simple perl or bash script that I will be using in my work as a junior bioinformatician.
Essentially, I would like to take a tab-delimted or .csv text with 3 columns and write them to a "3D" matrix:
... (16 Replies)
Discussion started by: torchij
16 Replies
9. Red Hat
Cheers!
In /etc/syslog.conf, if an error type is not specified, is it logged anywhere (most preferable is it logged to /var/log/messages) or not?
To be more precise I am interested in error and critical level messages. At default these errors are not specified in syslog.conf, and I need to... (6 Replies)
Discussion started by: dr1zzt3r
6 Replies
IO(4) BSD Kernel Interfaces Manual IO(4)
NAME
io -- I/O privilege file
SYNOPSIS
device io
#include <sys/types.h>
#include <sys/ioctl.h>
#include <dev/io/iodev.h>
#include <machine/iodev.h>
struct iodev_pio_req {
u_int access;
u_int port;
u_int width;
u_int val;
};
DESCRIPTION
The special file /dev/io is a controlled security hole that allows a process to gain I/O privileges (which are normally reserved for kernel-
internal code). This can be useful in order to write userland programs that handle some hardware directly.
The usual operations on the device are to open it via the open(2) interface and to send I/O requests to the file descriptor using the
ioctl(2) syscall.
The ioctl(2) requests available for /dev/io are mostly platform dependent, but there are also some in common between all of them. The
IODEV_PIO is used by all the architectures in order to request that an I/O operation be performed. It takes a 'struct iodev_pio_req' argu-
ment that must be previously setup.
The access member specifies the type of operation requested. It may be:
IODEV_PIO_READ The operation is an "in" type. A value will be read from the specified port (retrieved from the port member) and the result
will be stored in the val member.
IODEV_PIO_WRITE The operation is a "out" type. The value will be fetched from the val member and will be written out to the specified port
(defined as the port member).
Finally, the width member specifies the size of the operand to be read/written, expressed in bytes.
In addition to any file access permissions on /dev/io, the kernel enforces that only the super-user may open this device.
LEGACY
The /dev/io interface used to be very i386 specific and worked differently. The initial implementation simply raised the IOPL of the current
thread when open(2) was called on the device. This behaviour is retained in the current implementation as legacy support for both i386 and
amd64 architectures.
SEE ALSO
close(2), i386_get_ioperm(2), i386_set_ioperm(2), ioctl(2), open(2), mem(4)
HISTORY
The io file appeared in FreeBSD 1.0.
BSD
June 1, 2010 BSD