I'm using growisofs to write DVD, e.g.
$ growisofs -Z /dev/dvd -V "Personal Data, `date +"%b, %d %Y"`" -R -J /mnt/d/*
How can I test whether data was written correctly? md5sum or so? (0 Replies)
PROGRAM A <-> PROGRAM B
PROGRAM A sends data as STDIN ro PROGRAM B and when PROGRAM B is executed from PROGRAM A, it sends output back to PROGRAM A. This is implemented using 2 pipes (fd1 & fd2).
The above process happens in a loop and during the second run, the previous data that had been... (10 Replies)
Hello,
I have a script that monitors files uploaded via ftp. After a successful upload, the file name is written to the pipe.
There is another program that reads this pipe and allows automatically run any program or script ( say test.sh ) to process the newly uploaded file.
cat test.sh... (2 Replies)
$SYBASE/bin/isql -U $DB_USERID -S $DB_SERVER << ! >> $OUTFILE
`echo $DB_PASSWD`
use $db
go
Print " The processing"
go
!
# Extract data to file
echo $DB_PASSWD | $SYBASE/bin/bcp $WRK_DB..open out $CONV_DIR/open".csv -t\, -c -U $DB_USERID -S $DB_SERVER -b 1000 | tail -3
I am able to... (0 Replies)
The following is a piece of code to rename LOG_FILE_NEW to LOG_FILE once you get a result (either RUNNING or SHUTDOWN)
RESULT=""
sleep 30
while ; do
sleep 10
RESULT=`sed -n '/RUNNING/'p ${LOG_FILE_NEW}`
if ; then
RESULT=`sed -n '/SHUTTING_DOWN/'p ${LOG_FILE_NEW}`
fi
done
mv... (3 Replies)
Hi Everyone,
The machine I'm working on is an AIX 5.3 LPAR running on a P650. oslevel -r shows 5300-08. I'm trying to take a backup to a SCSI tape drive, which has been working up until this point. I know of nothing that has changed recently to cause this problem. But when I try to take a... (0 Replies)
We use SAP application cluster on AIX. Communication between 2 of its instances is failing randomly with the following error:
java.net.SocketException: There is no process to read data written to a pipe.
The above error causes a cluster restart if an important communication fails.
Can... (0 Replies)
In the hello.htm have the sentenses:
Hello $name
How are you?
The perl script:
$name = "David";
open(HEADER,"hello.htm");
while(<HEADER>) { $html .= $_; }
close(HEADER);
print "$html";I making something about template. But it can't process the $name variable. (4 Replies)
Hello,
I need to read the pipe data as:-
cat abc.txt | uuencode abc.txt | mailx -s hi xyz@xyz.com
I will override the mailx function so that when mailx is called, it calls my version of maix and in that function I want to read the file which is attached in progional mailx function- abc.txt... (7 Replies)
Hello All,
I am building a real time parser for a log file in my application.
The log file is continuously written at a very fast pace and gets rolled over every 10 minutes.
I have measured the speed and observed that around 1000 lines are written to it every second, each line about 30-40... (7 Replies)
Discussion started by: cool.aquarian
7 Replies
LEARN ABOUT NETBSD
pipe
PIPE(2) BSD System Calls Manual PIPE(2)NAME
pipe -- create descriptor pair for interprocess communication
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
int
pipe(int fildes[2]);
int
pipe2(int fildes[2], int flags);
DESCRIPTION
The pipe() function creates a pipe, which is an object allowing unidirectional data flow, and allocates a pair of file descriptors. The
first descriptor connects to the read end of the pipe, and the second connects to the write end, so that 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 program: the source's standard output is set
up to be the write end of the pipe, and the sink's standard input is set up to be the read end of the pipe. The pipe itself persists until
all 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 pipe2() function behaves exactly like pipe() only it allows extra flags to be set on the returned file descriptor. The following flags
are valid:
O_CLOEXEC Set the ``close-on-exec'' property.
O_NONBLOCK Sets non-blocking I/O.
O_NOSIGPIPE
Return EPIPE instead of raising SIGPIPE.
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() and pipe2() calls will fail if:
[EFAULT] The fildes buffer is in an invalid area of the process's address space. The reliable detection of this error cannot be
guaranteed; when not detected, a signal may be delivered to the process, indicating an address violation.
[EMFILE] Too many descriptors are active.
[ENFILE] The system file table is full.
pipe2() will also fail if:
[EINVAL] flags is other than O_NONBLOCK or O_CLOEXEC.
SEE ALSO sh(1), fork(2), read(2), socketpair(2), write(2)STANDARDS
The pipe() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').
HISTORY
A pipe() function call appeared in Version 6 AT&T UNIX. The pipe2() function is inspired from Linux and appeared in NetBSD 6.0.
BSD January 23, 2012 BSD
05-22-2009
(walks away whistling coyly)