BLK_EXECUTE_RQ_NOWAI(9) Block Devices BLK_EXECUTE_RQ_NOWAI(9)NAME
blk_execute_rq_nowait - insert a request into queue for execution
SYNOPSIS
void blk_execute_rq_nowait(struct request_queue * q, struct gendisk * bd_disk, struct request * rq, int at_head, rq_end_io_fn * done);
ARGUMENTS
q
queue to insert the request in
bd_disk
matching gendisk
rq
request to insert
at_head
insert request at head or tail of queue
done
I/O completion handler
DESCRIPTION
Insert a fully prepared request at the back of the I/O scheduler queue for execution. Don't wait for completion.
NOTE
This function will invoke done directly if the queue is dead.
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 BLK_EXECUTE_RQ_NOWAI(9)
Check Out this Related Man Page
mq_notify(3) Library Functions Manual mq_notify(3)NAME
mq_notify - Attaches a request for asynchronous signal notification to a message queue (P1003.1b)
LIBRARY
Realtime Library (librt.so, librt.a)
SYNOPSIS
#include <mqueue.h>
int mq_notify (
mqd_t mqdes,
const struct sigevent *notification);
PARAMETERS
mqdes Specifies a message queue descriptor.
*notification Specifies a signal to be sent when the specified queue accepts a message. If the notification argument is NULL, and the
process has previously attached a notification request to the message queue with this mqdes argument, the notification
request is detached and the queue is available for another process to attach a notification request.
DESCRIPTION
The mq_notify function attaches a request for asynchronous signal notification to a message queue for the calling process. Following a
call to this function, the specified signal is sent to the calling process when the queue transitions from empty to non-empty. Two or more
processes cannot attach notification requests to the same queue at the same time.
If a process has attached a notification request and any process is blocked in the execution of the mq_receive function waiting to receive
a message when a message arrives at the queue, then the appropriate mq_receive function is completed and the notification remains pending.
When the notification has been sent, the registration is canceled. In effect, it is a one-shot notification and must be re-registered if
required.
Note that the POSIX IPC functions are not reentrant with respect to signals. For example, if your application were to use a signal to
notify it that a queue has become non-empty and then attempt to call mq_receive from the signal handler, the signal handler must reside in
a thread other than the tread that called mq_send. Otherwise, a deadlock on internal locks would occur.
RETURN VALUES
On successful completion, the function returns the value 0 (zero); otherwise, the function returns the value -1 and sets errno to indicate
the error.
ERRORS
The mq_notify function fails under the following conditions:
[EBADF] The mqdes argument is not a valid message queue descriptor.
[EBUSY] A process has already attached to this message queue for asynchronous notification, or the calling process attempted to can-
cel a request that was attached by another process.
[EINVAL] The requested signo is invalid, or the sigev_notify field of the notification structure does not equal SIGEV_SIGNAL.
RELATED INFORMATION
Functions: mq_open(3), mq_send(3)
Guide to Realtime Programming delim off
mq_notify(3)
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 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)
hi all,
i have installed quota on my centos 7 machine and its what im after (setting size limit on users, so they cant fill the hard drive)
i want to now make this part of my create user script for my sftp server so i want to do a echo and a read command so i capture the limit they enter... (0 Replies)
Hi everybody,
Which Unix base OS have best performance for HOST virtualization?
I tested SmartOS but it needs another OS to connect remotely!
Thanks in advance. (11 Replies)
Hi All,
I need to write a shell script which opens a file and increments the version(text) within the file every time the script runs. For example:
$ cat docker_file.yml
version: '3.1'
services:
ui:
image: repo-srv.dev.io:5000/facebook/ui:0.0.2-QA1
$
So, I would like... (6 Replies)
Dear Team
We use DB2 v10.5 and using DBArtisan tool
Can someone please guide how to convert digits to binary numbers using db2 feature.
Ex> for number 9 , binary should be 1001 ( 8+1)
Any help appreciated. Thanks (2 Replies)
hi folks,
how to using tar with exclude directory and compress it using tar.Z
i only know how to exclude dir only with this command below:
tar -cvf /varios/restore/test.tar -X excludefile.txt /jfma/test1/
how to compress it using 1 command?
Thanx
Please use CODE tags as... (6 Replies)
Quite an obscure question I think.
We have a rebuild process for remote sites that allows us to PXE rebuild a till (actually a PC with a touch screen and various fancy bits) running CentOS. The current CentOS5 tills work just fine with a tar image restore and some personalisation. Sadly,... (4 Replies)
Hello All,
I had recently learnt a bit of Docker(which provides containerization process).
Here are some of my learning points from it.
Let us start first with very basic question:
What is Docker:
Docker is a platform for sysadmins and developers to DEPLOY, DEVELOP and RUN applications ... (7 Replies)
What is the point of this? Whenever I close my shell it appends to the history file without adding this. I have never seen it overwrite my history file.
# When the shell exits, append to the history file instead of overwriting it
shopt -s histappend (3 Replies)
Hello... And thanks in advance for any help anyone can offer me
I was trying to work out the differences between displaying modify, access, and change times with the 'ls' command. Everything seems in order when I look at files, but the access time on a directory doesn't seem to change when I... (4 Replies)
Hello everyone,
I am having an issue here with CentOS release 6.6 (Final) that shows all of the space used up, but I can't tell where the space went.
Seemingly I am using up 100%, according to
df -h
Filesystem Size Used Avail Use% Mounted on... (27 Replies)
I'm trying to use a bash script for a psych experiment that involves listening to sound files and responding. If I have something like the code below, how can I make sure that a key press is assigned to RESPONSE only after the second echo statement?
for i in 1 2 3; do
echo "Ready?"
sleep 2
... (10 Replies)
After the success of the jq - tool for parsing and manipulating JSON-Data someone wrote a tool called yq, which aims to be the same for YAML, what jq is for JSON. Seems to work fine. I'll definitely give it a chance in future.
Example YAML-File:
--- !ruby/object:Puppet::Node::Facts
... (1 Reply)
Dear All,
I am very pleased to announce that Dave Munro (gull04) is joining the Moderation Team, after being a very valuable member of UNIX.com for 15+ years.
Dave is an IT Consultant with 30 years of experience this year, has worked in many of the industry vertical market segments and has... (6 Replies)