I am attempting to automate an ftp session in PERL by emulating the user and sending commands to ftp, but I am getting unexpected and unwanted results. Here is a portion code that illustrates the method I am attempting (this was just a shot in the dark):
system("(
echo open server
sleep 1... (2 Replies)
Hi,
perhaps you can answer my question.....;)
How can I check, how many file handles are used and how can i increase the value for maximum file handles??? (3 Replies)
Hi all
I try to execute SSH commands on several hosts in a while-loop.
There seems to be a problem with file-handle, first cycle works correct but no other one will follow due to the while condition is false even that there are many more host entries (lines) in all_hosts.dat.
... (3 Replies)
We have a process that is running out of file handles. Is there some command line way to determine this that we can include into a cron script?
Please let me know
JAK (3 Replies)
Hi Thinkers,
On AIX 5.3, we have a monitor program that reads the log file and searching for a certain string pattern that we define(say "transactionException"), if it sees it then it will raise an alert by sending an email.
Because the log file XXX.log is rolling into XXX.log.0, XXX.log.1,... (2 Replies)
I'm using Sendmail 8.13.8 on a CentOS 5.5 vServer (Virtuozzo).
I'm using a loop in PHP to send a lot of HTML-mails via sendmail. Each mail is a mail with individual statistics for our users, so its not mass mailing, bcc is not an option.
It all works fine, but when I take a closer look there... (2 Replies)
I want to have a message send & receive through 2 half-duplex pipes
Flow of data
top half pipe
stdin--->parent(client) fd1--->pipe1-->child(server) fd1
bottom half pipe
child(server) fd2---->pipe2--->parent(client) fd2--->stdout
I need to have boundary structed message... (1 Reply)
Hi ,
I just write a simple function to read the file line by line.
But when I run it it says out of memory.
I am not sure about the root cause, Can someone help me out of this?
:D
#! /usr/bin/perl
use strict;
sub checkAPs{
my $NDPDir = "/home/eweiqqu/NCB/NDP_files/";
... (1 Reply)
This is a strange one.
We have an issue where our system is leaking SCTP file handles. There are people working on this and in the mean time we have a monitoring script that alarms when we need to perform actions to manually clear them. For testing purposes I want to write a script that... (0 Replies)
Hello all!
This is my first post and I'm very new to programming. I would like help creating a simple perl or bash script that I will be using in my work as a junior bioinformatician.
Essentially, I would like to take a tab-delimted or .csv text with 3 columns and write them to a "3D" matrix:
... (16 Replies)
Discussion started by: torchij
16 Replies
LEARN ABOUT BSD
pipe
PIPE(2) System Calls Manual PIPE(2)NAME
pipe - create an interprocess communication channel
SYNOPSIS
pipe(fildes)
int fildes[2];
DESCRIPTION
The pipe system call creates an I/O mechanism called a pipe. The file descriptors returned can be used in read and write operations. When
the pipe is written using the descriptor fildes[1] up to 4096 bytes of data are buffered before the writing process is suspended. A read
using the descriptor fildes[0] will pick up the data.
It is assumed that after the pipe has been set up, two (or more) cooperating processes (created by subsequent fork calls) will pass data
through the pipe with read and write calls.
The shell has a syntax to set up a linear array of processes connected by pipes.
Read calls on an empty pipe (no buffered data) with only one end (all write file descriptors closed) returns an end-of-file.
Pipes are really a special case of the socketpair(2) call and, in fact, are implemented as such in the system.
A signal is generated if a write on a pipe with only one end is attempted.
RETURN VALUE
The function value zero is returned if the pipe was created; -1 if an error occurred.
ERRORS
The pipe call will fail 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.
SEE ALSO sh(1), read(2), write(2), fork(2), socketpair(2)BUGS
Should more than 4096 bytes be necessary in any pipe among a loop of processes, deadlock will occur.
4th Berkeley Distribution August 26, 1985 PIPE(2)
05-06-2007
