which hangs on the final echo command when I run it.
Interestingly, if I comment out the ls, or either echo command, it works fine.
So I'm trying to understand what's happening here. Hoping somebody could explain?
What I'm trying to do:
- capture stdout and stderr into a log file. [edit] correction: want to capture stdout and sterr to both display and log file[/edit]
- need to capture the return code of the command as well (ie $?) (hence why I'm mucking around with PIPE's so I can displace the tee command).
It seems to work sometimes, and then hang on other occasions, and I haven't found a pattern to it yet.
Hoping anyone can shed light on this - or provide a suitable work around.
Thanks!
[edit]
more specific version info:
Sun4u sparc SUNW
SPARC-Enterprise SunOS
5.10
uname -v
returns:
Generic_147440-02
[/edit]
[edit]
Seems as soon as I do an ls, cp, mv or other disk access, it hangs on the next command?
[/edit]
Last edited by Ditto; 03-19-2014 at 05:19 PM..
Reason: version
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)
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)
I would like to pipe (redirect ? - what is the right term?) the output of my script to a file named with the current date.
If I run this at a command prompt:
date +'%Y%m%d"
...it returns "20110429"
OK, that's good... so I try:
./script.sh > "'date +%Y%m%d'.csv"
I get a file... (1 Reply)
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:
#!/bin/ksh
mkfifo pipe
while (( n <= 10 ))
do
echo... (2 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)
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 OSX
pipe
PIPE(2) BSD System Calls Manual PIPE(2)NAME
pipe -- create descriptor pair for interprocess communication
SYNOPSIS
#include <unistd.h>
int
pipe(int fildes[2]);
DESCRIPTION
The pipe() function creates a pipe (an object that allows unidirectional data flow) and allocates a pair of file descriptors. The first
descriptor connects to the read end of the pipe; the second connects to the write end.
Data written to fildes[1] appears on (i.e., can be read from) fildes[0]. This allows the output of one program to be sent to another pro-
gram: the source's standard output is set up to be the write end of the pipe; the sink's standard input is set up to be the read end of the
pipe. The pipe itself persists until all of its associated descriptors are closed.
A pipe whose read or write end has been closed is considered widowed. Writing on such a pipe causes the writing process to receive a SIGPIPE
signal. Widowing a pipe is the only way to deliver end-of-file to a reader: after the reader consumes any buffered data, reading a widowed
pipe returns a zero count.
The generation of the SIGPIPE signal can be suppressed using the F_SETNOSIGPIPE fcntl command.
RETURN VALUES
On successful creation of the pipe, zero is returned. Otherwise, a value of -1 is returned and the variable errno set to indicate the error.
ERRORS
The pipe() call will fail if:
[EFAULT] The fildes buffer is in an invalid area of the process's address space.
[EMFILE] Too many descriptors are active.
[ENFILE] The system file table is full.
SEE ALSO sh(1), fork(2), read(2), socketpair(2), fcntl(2), write(2)HISTORY
A pipe() function call appeared in Version 6 AT&T UNIX.
4th Berkeley Distribution February 17, 2011 4th Berkeley Distribution
03-19-2014
Named pipe hanging?
