I am trying to read stdout from a child process to parent using pipe. I am unable to do so. I would appreciate it if someone can point me in the right direction.
Here's my sample program for basic input output:
The program that calls fork():
The output of tp:
What I would like : I want ./tp to print out "first:" before the prompt for input. Basically, it should emulate ./sss.
Hi there
I know that this isn't the place to put a question like this i supose, but i'm geting desperated. I have searched in interbase forums and nothing helped. If anyone can help me i would apreciated.
I'm using HP-UX with a version 3 of interbase wich means i can't split the backup file into... (3 Replies)
Hi!!
I have a problem reading from a fifo pipe in shell script.
The idea is simple, I have a C program with two pipe files:
An input pipe I use to send commands in shell script to the C program (echo "command" > input.pipe)
An output pipe that I read the result of the command also in... (4 Replies)
hi
iam reading data from web page using request socket and curl socket.
now my problem is some the web page containg data as a image so how can i read the data from a image.
thank,inadvance.
sree (3 Replies)
Hi,
Program A: uses pipe()
I am able to read the stdout of PROGAM B (stdout got through system() command) into PROGRAM A using:
* child
-> dup2(fd, STDOUT_FILENO);
-> execl("/path/PROGRAM B", "PROGRAM B", NULL);
* parent
-> char line;
-> read(fd, line, 100);
Question:... (2 Replies)
Hi,
I am new to UNIX shell scripting (KSH). I have a file in UNIX server which is delimited by |.
I require the basic syntax to:
read the file
move it to a local variables
load a database - Teradata
Continue until end of file.
Note: if the field is have no value inbetween two... (6 Replies)
I'm trying to read a fifo using awk and comming across some problems. I'm writing to the fifo from multiple processes invoked by GNU Parallel:
mkfifo my_fifo
awk '{ a = a + $2 } END { for (i in a) print i, a }' my_fifo | sort -nk1 > sorted_output
grep -v '^@' massive_file | parallel... (3 Replies)
Hi Guys,
i am reading a pipe delimited file using awk command.
I have tested the gawk separately. it was fine.
But when i execute the script. i am getting the following error saying command not found.
Can somebody point out as what i am doing wrong.
Cheers!!! (3 Replies)
Hi,
I have a program set to read in a text file, change certain characters and then print the altered version to the screen but does anyone know how to save the new version as another text file? And, if possible, how to specify the file name, and perhaps location?
Thanks! (2 Replies)
Hi guys,
I need to know how i can ignore Pipe '|' if Pipe is coming as a column in Pipe delimited file
for eg:
file 1:
xx|yy|"xyz|zzz"|zzz|12...
using below awk command
awk 'BEGIN {FS=OFS="|" } print $3
i would get xyz
But i want as :
xyz|zzz to consider as whole column... (13 Replies)
Discussion started by: rohit_shinez
13 Replies
LEARN ABOUT DEBIAN
io::async::pid
IO::Async::PID(3pm) User Contributed Perl Documentation IO::Async::PID(3pm)NAME
"IO::Async::PID" - event callback on exit of a child process
SYNOPSIS
use IO::Async::PID;
use POSIX qw( WEXITSTATUS );
use IO::Async::Loop;
my $loop = IO::Async::Loop->new;
my $kid = $loop->fork(
code => sub {
print "Child sleeping..
";
sleep 10;
print "Child exiting
";
return 20;
},
);
print "Child process $kid started
";
my $pid = IO::Async::PID->new(
pid => $kid,
on_exit => sub {
my ( $self, $exitcode ) = @_;
printf "Child process %d exited with status %d
",
$self->pid, WEXITSTATUS($exitcode);
},
);
$loop->add( $pid );
$loop->run;
DESCRIPTION
This subclass of IO::Async::Notifier invokes its callback when a process exits.
For most use cases, a IO::Async::Process object provides more control of setting up the process, connecting filehandles to it, sending data
to and receiving data from it.
EVENTS
The following events are invoked, either using subclass methods or CODE references in parameters:
on_exit $exitcode
Invoked when the watched process exits.
PARAMETERS
The following named parameters may be passed to "new" or "configure":
pid => INT
The process ID to watch. Must be given before the object has been added to the containing "IO::Async::Loop" object.
on_exit => CODE
CODE reference for the "on_exit" event.
Once the "on_exit" continuation has been invoked, the "IO::Async::PID" object is removed from the containing "IO::Async::Loop" object.
METHODS
$process_id = $pid->pid
Returns the underlying process ID
$pid->kill( $signal )
Sends a signal to the process
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.14.2 2012-10-24 IO::Async::PID(3pm)