IEEE1284_REF(3) Functions IEEE1284_REF(3)NAME
ieee1284_ref, ieee1284_unref - modify a port's reference count
SYNOPSIS
#include <ieee1284.h>
int ieee1284_ref(struct parport *port);
int ieee1284_unref(struct parport *port);
DESCRIPTION
If you want to free the port list from ieee1284_find_ports but open one of the ports later on, you will need to prevent it from being
destroyed in ieee1284_free_ports. Each port has a reference count, and you can use ieee1284_ref to increment it and ieee1284_unref to
decrement it.
If you use ieee1284_ref at any stage, you must later call ieee1284_unref to relinquish the extra reference. If you do not do this, the
resources associated with the port will not be cleaned up.
If you have not previously used ieee1284_ref on a port, you must not use ieee1284_unref on it.
RETURN VALUE
These functions return the number of references held after the increment or decrement.
SEE ALSO ieee1284_open(3)AUTHOR
Tim Waugh <twaugh@redhat.com>
Author.
COPYRIGHT
Copyright (C) 2001-2003 Tim Waugh
09/18/2007 IEEE1284_REF(3)
Check Out this Related Man Page
IEEE1284_GET_IRQ_FD(3) Functions IEEE1284_GET_IRQ_FD(3)NAME
ieee1284_get_irq_fd, ieee1284_clear_irq - interrupt notification
SYNOPSIS
#include <ieee1284.h>
int ieee1284_get_irq_fd(struct parport *port);
int ieee1284_clear_irq(struct parport *port, unsigned int *count);
DESCRIPTION
If the port has a configured interrupt line and the port type supports interrupt notification, it is possible to obtain a file descriptor
that may be used for select(2) or poll(2). Any event (readable, writable or exception) means that an interrupt has been triggered. No
operations other than select or poll may be performed on the file descriptor.
The port must be open in order to call ieee1284_get_irq_fd, and must be claimed when using select or poll.
The caller must not close the file descriptor, and may not use it at all when the port is not claimed.
When an interrupt has been detected, the caller must call ieee1284_clear_irq to clear the interrupt condition, at which point the number of
interrupts raised can be obtained by supplying a non-NULL count.
RETURN VALUE
For ieee1284_get_irq_fd: If the return value is negative then it is an error code listed below. Otherwise it is a valid file descriptor.
E1284_NOTAVAIL
No such file descriptor is available.
E1284_INVALIDPORT
The port parameter is invalid (for instance, perhaps the port is not open).
For ieee1284_clear_irq:
E1284_OK
The interrupt has been cleared. If count was not NULL the count of interrupts has been atomically stored to count and reset.
E1284_NOTAVAIL
The count parameter was not NULL but interrupt counting is not supported on this type of port. The interrupt has been cleared.
E1284_SYS
There was a problem clearing the interrupt.
E1284_INVALIDPORT
The port parameter is invalid (for instance, perhaps the port is not claimed).
AUTHOR
Tim Waugh <twaugh@redhat.com>
Author.
COPYRIGHT
Copyright (C) 2001-2003 Tim Waugh
09/18/2007 IEEE1284_GET_IRQ_FD(3)
I have a huge matrix file containing some 1.5 million rows and 6000 columns. The matrix looks something like this:
1 2 3
4 5 6
7 8 9
3 4 5
I want to add all the numbers in the columns of this matrix and display the result to my stdout. This means that the numbers in the first column are:
... (2 Replies)
Hi,
Just trying to get to grips with sed and awk for some reporting for work and I need some assistance:
I have a file that lists policy names on the first line and then on the second line whether the policy is active or not.
Policy Name: Policy1
Active: yes
Policy... (8 Replies)
version info :
vi availabe with RHEL 5.4
I have a text file with 10,000 lines. I want to copy lines from 5000th line to 7000th and redirect to a file. Any idea how I can do this?
Note:
The above scenario is just an example. In my actual requirement, the file has 14 million lines and I want... (9 Replies)
Hi everyone,
I know the following questions are noobish questions but I am asking them because I am confused about the basics of history behind UNIX and LINUX.
Ok onto business, my questions are-:
Was/Is UNIX ever an open source operating system ?
If UNIX was... (21 Replies)
Hello,
I couldn't find an actual introduction thread, so I decided to just put this here.
I go by d0wngrade online. I have been programming in multiple languages for about 15+ years. I started with standard web design languages like HTML and CSS, but I then advanced from design to development... (2 Replies)
Hi guys...
The first active code line in AudioScope.sh is set -u .
This causes a complete exit if a variable is used/found but has not been allocated at the start of the program.
However, apart from writing code to do the task, is there a switch to to check which variables have been... (17 Replies)
Hi.
In thread https://www.unix.com/shell-programming-and-scripting/267833-grouping-counting.html rovf and I had a mini-discussion on grep and awk.
Here is a demo script that compares the awk and grep approaches for this single problem:
#!/usr/bin/env bash
# @(#) s2 Demonstrate group... (1 Reply)
Hello,
I have to fish out some specific columns from a file based on the header value. I have the list of columns I need in a different file. I thought I could read in the list of headers I need,
# file with header names of required columns in required order
headers_file=$2
# read contents... (11 Replies)
For those interested in installing dash shell on OSX Lion to help test POSIX compliancy of shell scripts, it is quite easy. I did it like this:
If you don't have gcc on your system:
0. Download and install the Command Line Tools for Xcode package from Sign In - Apple *
1. Download the dash... (2 Replies)
Hello and thanks in advance for any help anyone can offer me
I'm trying to learn the find command and thought I was understanding it... Apparently I was wrong. I was doing compound searches and I started getting weird results with the -size test. I was trying to do a search on a 1G file owned by... (14 Replies)
I have data of an excel files as given below,
file1
org1_1 1 1 2.5 100
org1_2 1 2 5.5 98
org1_3 1 3 7.2 88
file2
org2_1 1 1 2.5 100
org2_2 1 2 5.5 56
org2_3 1 3 7.2 70
I have multiple excel files as above shown.
I have to copy column 1, column 4 and paste into a new excel file as... (26 Replies)
Dear All,
Taking a break from Vue.js coding for the site, SEO and YT videos; and hopefully addressing some well deserved criticism from some here that I have been too focused on the visual aspects of the forums versus the substance and the community....
While the "current generation... (9 Replies)
Hi all...
Well guys and gals, I jumped in at the deep end and found things that PERL cannot do by default.
Many tricky terminal escape codes are not catered for so I had to create workarounds.
One thing I searched for was this:
Passing perl variable to shell command
AND, @Neo this was... (15 Replies)