Sponsored Content
Full Discussion: File read/ write operation
Operating Systems Linux File read/ write operation Post 302425303 by jim mcnamara on Thursday 27th of May 2010 02:57:39 PM
Old 05-27-2010
Is the object request.readyState in shared memory - can both reader and writer process see exactly the same object? If not then there needs to be a way using IPC to get the other process to see request.readyState.

If this is so and you don't like IPC:
You have to use advisory file locking - period. Since you're in C it ain't hard.
 

10 More Discussions You Might Find Interesting

1. IP Networking

how do you get to know if the write operation was succesful.

how do you get to know if the write operation for writing to a socket was succesful was succesful. (3 Replies)
Discussion started by: arjunjag
3 Replies

2. Shell Programming and Scripting

read and write from a file

I have tried to show the file name whose size is greater than 200 byte in current directory. Please help me. ls -l | tr -s " " " " | cut -f 5,9 -d " " >out.txt #set -a x `cat out.txt` i=0 `cat out.txt` | while do read x echo $x #re=200 j=0 if }" < "200" ] then echo $j j=`expr $j... (2 Replies)
Discussion started by: rinku
2 Replies

3. UNIX for Dummies Questions & Answers

Simultaneous file read operation

Hi All, I need information on file handling in UNIX enviornment. If in UNIX enviornment I have two process.. P1 P2 Both accessing the same file simultaneosuly(read operation).. Suppose P1 opened the file in read mode first and started reading the file.. Then P2 opens the same file in... (5 Replies)
Discussion started by: chibob
5 Replies

4. UNIX for Dummies Questions & Answers

Write/read to file descriptors

Is it possible to write to file descriptor 0 and read from 1 or 2? How could this be implemented? (3 Replies)
Discussion started by: machshev
3 Replies

5. Solaris

monitoring multipath IO for read and write operation

Hi Folks, I would like to monitor multipath IO on solaris for write and read operations. Does "sar -d" include multipath IO information along with other block devices ? Thanks, Faizan. (0 Replies)
Discussion started by: sifaizan
0 Replies

6. IP Networking

read/write,write/write lock with smbclient fails

Hi, We have smb client running on two of the linux boxes and smb server on another linux system. During a backup operation which uses smb, read of a file was allowed while write to the same file was going on.Also simultaneous writes to the same file were allowed.Following are the settings in the... (1 Reply)
Discussion started by: swatidas11
1 Replies

7. Shell Programming and Scripting

Transferring file write operation to another host

I have a process running on two hosts in Active/Standby mode. Process running on active machine is handling the traffic while process running on Standby machine is sitting idle. We have a debugging mechanism in which logs are generated on local machine. When logging is enabled then process running... (1 Reply)
Discussion started by: akhilonnet
1 Replies

8. Shell Programming and Scripting

Grab data between 2 keywords any do an array operation and write the file intact

Hi Unix Gurus, I need to grep for a block that is between a start and end keyword and then in between I need to find and replace a keyword. for eg: I need to search between Test = 000; and Test = 000; and find K9 and replace with M9 INPUT FILE Define { Replace = K9; Test =... (6 Replies)
Discussion started by: naveen@
6 Replies

9. Shell Programming and Scripting

File Read and Write

I have got a file in following format: AAAAAAA BBBBBBBB CCCCCCC DDDDDDD I am trying to read this file and out put it in following format: AAAAAAA,BBBBBBB,CCCCCCC,DDDDDD Preferred method is shell or Perl. Any help appreciated. (11 Replies)
Discussion started by: Araoki
11 Replies

10. Shell Programming and Scripting

Read and write in the file

Hello Guys, How all are doing? I have an issue in Unix and want help from all of you I have a file in UNIX which it read by line by line , If at the end of line '0' is written the it should fetch that line into another file and change '0' to '1' and If at the end of line '1' is written then it... (10 Replies)
Discussion started by: adisky123
10 Replies
IPCS(1) 						    BSD General Commands Manual 						   IPCS(1)

NAME
ipcs -- report System V interprocess communication facilities status SYNOPSIS
ipcs [-abcMmopQqSsTt] DESCRIPTION
The ipcs utility provides information on System V interprocess communication (IPC) facilities on the system. The options are as follows: -a Show the maximum amount of information possible when displaying active semaphores, message queues, and shared memory segments. (This is shorthand for specifying the -b, -c, -o, -p, and -t options.) -b Show the maximum allowed sizes for active semaphores, message queues, and shared memory segments. The ``maximum allowed size'' is the maximum number of bytes in a message on a message queue, the size of a shared memory segment, or the number of semaphores in a set of semaphores. -c Show the creator's name and group for active semaphores, message queues, and shared memory segments. -M Display system information about shared memory. -m Display information about active shared memory segments. -o Show outstanding usage for active message queues, and shared memory segments. The ``outstanding usage'' is the number of messages in a message queue, or the number of processes attached to a shared memory segment. -p Show the process ID information for active semaphores, message queues, and shared memory segments. The ``process ID information'' is the last process to send a message to or receive a message from a message queue, the process that created a semaphore, or the last process to attach or detach a shared memory segment. -Q Display system information about messages queues. -q Display information about active message queues. -S Display system information about semaphores. -s Display information about active semaphores. -T Display system information about shared memory, message queues and semaphores. -t Show access times for active semaphores, message queues, and shared memory segments. The access times is the time of the last con- trol operation on an IPC object, the last send or receive of a message, the last attach or detach of a shared memory segment, or the last operation on a semaphore. If none of the -M, -m, -Q, -q, -S, or -s options are specified, information about all active IPC facilities is listed. RESTRICTIONS
System data structures may change while ipcs is running; the output of ipcs is not guaranteed to be consistent. BUGS
This manual page is woefully incomplete, because it does not at all attempt to explain the information printed by ipcs. SEE ALSO
ipcrm(1) AUTHORS
Thorsten Lockert <tholo@sigmasoft.com> BSD
June 18, 1994 BSD
All times are GMT -4. The time now is 04:44 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy