In this post, java development India based experts will explain the concept of Quartz. You will also learn the method of setting up the Quartz in this article. You can ask experts if anything bothers you. Technology Quartz is the open source Java technology for scheduling background jobs. If we want to execute the task
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Tag: error
How to Upload Large Files to Amazon S3 with AWS CLI
Posted onAmazon S3 is a widely used public cloud storage system. S3 allows an object/file to be up to 5TB which is enough for most applications. The AWS Management Console provides a Web-based interface for users to upload and manage files in S3 buckets. However, uploading a large files that is 100s of GB is not
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How to Clean RAID Signatures on Linux
Posted onRAID systems such as MegaRAID add signatures to disks to maintain the infomration on these didks. When we simply remove these disks and install them to another server, Linux on the new server may detect these RAID signature infomration and refuses to continue write to the disk. Here is one example that mkfs reports “apparently
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How to Get Available Filesystem Space on Linux: a C Function with a C++ Example
Posted onIt is common for programs to write to files in filesystems on disks. However, what if the disk was almost full when your program writes to the filesystem on a disk? For systems software and mission critical programs, it is a better or must-to-do practice to check the available filesystem space before actually writing to
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RAII-like Error Handling and Resource Management in C
Posted onError handling and resource management are pervasive in programs. RAII originated in C++ is great. With RAII, it is much easier to write easy-to-read code that allocats/deallocats resources in the constructor/destructors. By representing a resource with a local object, we are sure that local object’s destructor will release the resource and will not forget to
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fclose – Close a Stream
Posted onfclose is a frequently used C standard library which closes the file associated with the stream and disassociates it. NAME fclose – close a stream SYNOPSIS #include <stdio.h> int fclose(FILE *fp); DESCRIPTION The fclose() function will flushes the stream pointed to by fp (writing any buffered output data using fflush()) and closes the underlying file
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How to Change the Site’s Default 404 Error Not Found Page
Posted onThe apache’s default “404 Error not found” page seems ugly. And may some hosting service put theire ads in it. We can add some entry in .htaccess to change the defualt 404 error page. This method can also be used for some other error codes. A list of the server returned codes can be found
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Emacs Tips and Howtos
Posted onWith Emacs, I feel happy. I love the rich functions of Emacs, such as compiling, quickly jumping to the lines with compilation error and debugging with gdb, and more. I ever wrote small tips posts about Emacs before. But it is a good idea to put them together and keep adding new ones. Here comes
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pkill and pgrep: Process Management Commands
Posted onThis is a introduction to *nix’s process management tools: pkill and pgrep. As this site’s domain name was pkill.info, a introduction to pkill should exist here. NAME pgrep, pkill – look up or signal processes based on name and other attributes SYNOPSIS pgrep [-flvx] [-d delimiter] [-n|-o] [-P ppid,…] [-g pgrp,…] [-s sid,…] [-u euid,…]
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Setting up Stable Xen Dom0 with Fedora: Xen 3.4.3 with Xenified Linux Kernel 2.6.32.13 in Fedora 12
Posted onThis is the latest stable and recommended stable Xen Dom0 solution on Fedora 12. No serious bug found till now and we will fix the bugs by ourselves if some appears. It also works on Fedora 14 as well. It should not be hard to use this solution on other versions of Fedora or other
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Problems during Installing Xen Dom0 in Fedora
Posted onHere is a list of problem that may occur during installing and configuring Xen Dom0 in Fedora. It is found originally in Fedora systems, but the tips in this post should also be helpful for installing Xen Dom0 on other platforms. BIOS configuration If xen stops at: “I/O virtualization disabled.” We may need to enable
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Setting Up a NFS Server on Top of tmpfs /dev/shm
Posted ontmpfs has blazing speed. Why not set up a high speed NFS server on top of tmpfs? A little trick is required for setting NFS server on top of /dev/shm. If we add a normal entry in /etc/export and them run # exportfs -a exportfs will give us a warning like this: exportfs: Warning: /dev/shm
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Howto: Git Server over SSH
Posted onGit and SSH are both powerful tools, and git/ssh work well together. We introduce how to set up git server via ssh in this post. Git server through SSH is easy and fast to set up, although every user will have access to all repositories in the git server over SSH and every user is
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Hadoop Installation Tutorial (Hadoop 1.x)
Posted onUpdate: If you are new to Hadoop and trying to install one. Please check the newer version: Hadoop Installation Tutorial (Hadoop 2.x). Hadoop mainly consists of two parts: Hadoop MapReduce and HDFS. Hadoop MapReduce is a programming model and software framework for writing applications, which is an open-source variant of MapReduce that is initially designed
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