Hi,
I want to use a Named pipe to get input from a growing file for further processing. When I prototype this scenario using a while loop, the data is not written to the named pipe.
This the script I use to get data into the Named pipe:
I have not used Named pipe before. I am not sure what I am missing. Please help.
Hi All,
I am facing a vague issue while trying to make two process talk to each
other using named pipe.
read process
=========
The process which reads, basically creates FIFO using
mkfifo - ret_val = mkfifo(HALF_DUPLEX, 0666);) func.
It then opens the pipe using open func - fd =... (1 Reply)
Hi All,
I am facing a vague issue while trying to make two process talk to each
other using named pipe.
read process
=========
The process which reads, basically creates FIFO using
mkfifo - ret_val = mkfifo(HALF_DUPLEX, 0666) func.
It then opens the pipe using open func - fd = open... (2 Replies)
Gurus,
I've a File Transaction Server, which communicates with other servers and performs some processing.It uses many Named PIPE's.
By mistake i copied a named PIPE into a text file.
I heard that PIPE files shouldn't be copied.Isn't it?
Since it's a production box, i'm afraid on... (2 Replies)
I want to copy the contents of a named pipe to a file. I have tried using:
cat pipe.p >> transcript.log
but I have been unsuccessful, any ideas? (4 Replies)
I did
cat < myFile >> myPipe
I was hoping that if I did ls -l, myPipe would now be holding the contents of myFile, and would be the same size. But it was 0.
Also strange was that when I did the command above, cat did not return control back to the shell. Why?
thanks (4 Replies)
Hello,
On my machine, all mail is stored in my /var/spool/mail.
IS there a way to direct all mail that goes there into a namep pipe?
Thank you,
Dado (4 Replies)
Hi,
I am getting data into a Named pipe. Does Named pipe have any size restriction; I know it does not have any storage and it just passes on the data to the next process.
I want to know, if there will be a difference in the Named pipe performance if the data input is more. (I am using DB2... (1 Reply)
Hi All !
I try to collect importent events from syslog and in my
syslog conf, there is something like this:
*.* |/logs/ipes/SLpipe1
I have a program, which opens this pipe and reads the messages from it.
But how this pipe works ? Where can I probably read something about the details,... (3 Replies)
Ok, I can't seem to figure this out or find anything on the web about this.
I'm on Sun Solaris, UNIX.
I have the following test script:
#!/bin/ksh
touch test.file
LOG=./tmp.log
rm -f ${LOG}
PIPE=./tmp.pipe
mkfifo ${PIPE}
trap "rm -f ${PIPE}" EXIT
tee -a ${LOG} < ${PIPE} &
... (17 Replies)
Hi ALL,
How can I test a given file name exists and if it is a named pipe file in shell script ?
Thanks............ (2 Replies)
Discussion started by: mycode.in
2 Replies
LEARN ABOUT ULTRIX
pipe
pipe(2) System Calls Manual pipe(2)Name
pipe - create an interprocess channel
Syntax
include <limits.h> /*Definition of PIPE_MAX*/
pipe(fildes)
int fildes[2];
Arguments
fildes Passing an address as an array of two integers into the system call.
Description
The system call creates an I/O mechanism called a pipe. The file descriptors returned can be used in and operations. Their integer values
will be the two lowest available at the time of the function call. The O_NONBLOCK and FD_CLOEXEC flags will be clear on both file descrip-
tors.
When the pipe is written using the descriptor fildes[1], up to PIPE_MAX bytes of data are buffered before the writing process is suspended.
A read using the descriptor fildes[0] picks up the data.
It is assumed that after the pipe has been set up, two (or more) cooperating processes (created by subsequent calls) pass data through the
pipe with and calls.
The shell has a syntax to set up a linear array of processes connected by pipes.
For further information on how and calls behave with pipes, see the and reference pages.
A signal is generated if a write on a pipe with only one end is attempted.
Restrictions
Should more than 4096 bytes be necessary in any pipe among a loop of processes, deadlock may occur.
The underlying implementation of pipes is no longer socket based, but rather implemented through the file system. Any application that
needs socket functionality from pipes should use the system call.
Return Values
The function value zero is returned if the pipe was created; -1 if an error occurred.
Diagnostics
The call fails if:
[EMFILE] Too many descriptors are active.
[ENFILE] The system file table is full.
[EFAULT] The fildes buffer is in an invalid area of the process's address space.
Environment
Differs from the System V definition in that ENFILE is not a possible error condition.
See Alsosh(1), fork(2), read(2), socketpair(2), write(2)pipe(2)