Skip to main content

lsof command and options

lsof - list open files. An  open file may be a regular file, a directory, a block special file, a character special file, an executing text reference, a library, a stream or a network file (Internet socket, NFS file or UNIX domain socket.)  A specific file or all the files in a file system may be selected by path. Given that this command identifies which files are being used, this information can be used when disk can not be unmounted due to files being used or opened.
Type the following command:
$lsof
    lsof.png
Herein -
FD – stands for File descriptor and may have some of the values as:
  1. cwd current working directory
  2. rtd root directory
  3. txt program text (code and data)
  4. mem memory-mapped file
Also in FD column numbers like 41u is actual file descriptor and followed by u,r,w of it’s mode as:
  1. r for read access.
  2. w for write access.
  3. u for read and write access.
TYPE – of files and it’s identification.
  1. DIR – Directory
  2. REG – Regular file
  3. CHR – Character special file.
  4. FIFO – First In First Out
  5. IPv4
  6. IPv6
OPTIONS
-u s selects the listing of files for the user whose login names or user ID numbers are in the comma-separated set s -  e.g.,  ``abe'', or ``548,root''.  (There should be no spaces in the set.)
    $lsof -u tarun
-i [i] selects the listing of files any of whose Internet address matches the address specified in i. If no address is specified, this option selects the listing of all Internet and x.25 (HP-UX) network files. Following command lists all network connections listening and established -
$lsof -i
Screenshot from 2015-07-22 14:35:31.png
An Internet address is specified in the form (Items in square brackets are optional.):
[46][protocol][@hostname|hostaddr][:service|port]
    $lsof -i TCP:80
Screenshot from 2015-07-22 14:13:46.png
List running processes of open files of TCP port range from 1-800
    $lsof -i TCP:1-800
Screenshot from 2015-07-22 14:25:27.png
If -i4 or -i6 is specified with no following address, only files of the indicated IP version, IPv4 or IPv6,  are  displayed.
    $lsof -i4
    Screenshot from 2015-07-22 14:22:02.png
    $lsof -i6
Screenshot from 2015-07-22 14:22:30.png

-p s excludes or selects the listing of files for the processes  whose  optional  process  IDentification  (PID)  numbers  are  in  the comma-separated set s - e.g., ``123'' or ``123,^456''.  (There should be no spaces in the set.) PID numbers that begin with `^' (negation) represent exclusions.

        $lsof -p 2499

-t   specifies  that  lsof  should  produce  terse output with process identifiers only and no header - e.g., so that the output may be piped to kill(1)

        $lsof -p 2499

        $kill -9 `lspf -t -u tarun`
Labels:

Popular posts from this blog

Verify email confirmation using Selenium WebDriver

Note: If you are new to java and selenium then start with selenium java training videos .   How to Verify Email Confirmation Using Selenium 4 and JavaMail (2026 Guide) Email confirmation is a critical part of most registration flows — account activation, password reset, multi-factor authentication, and onboarding. Every automation engineer eventually faces the same challenge: How do you verify an email confirmation link inside a Selenium test without making it slow and flaky? The wrong instinct is to automate Gmail's UI with Selenium. It's fragile, slow, and breaks constantly. The right approach: Use Selenium for browser automation Use JavaMail (IMAP) to read the email directly Extract the confirmation link Continue the test in Selenium Why Not Automate Gmail UI With Selenium? Automating the Gmail UI means logging in, searching, clicking a message, and parsing content from a third-party interface that changes frequently. This leads to: Flaky...
13 comments
Read more

Real Time JMeter Result Using Backend Listener

Since JMeter 2.13 Backend Listener has been available to create real time graph of JMeter Test. Following tutorial explain the entire process in detail. At the end of this tutorial you would be able to create JMeter Live Test Result dashboard similar to following - This tutorial borrows information from many sources and my own experiments with JMeter live reporting dashboard. I have added source of information wherever applicable But before we can build such a snazzy JMeter Live Reporting dashboard we need to understand two more components - influxDB (a time series database) and Grafana Dashboard This is a big tutorial, so take deep breath :-) and follow on. Once you complete set up specified in this tutorial then you can watch JMeter Training Video Tutorial to watch this in action. What is Time Series Database? A time series is a sequence of data points , typically consisting of successive measurements made over a time interval . Examples of time ...
Read more

Using xPath to reach parent of an element

Note: If you are new to java and selenium then start with selenium java training videos .   I generally prefer CSS selectors over XPath when writing Selenium locators. CSS selectors are concise, readable, and usually provide everything I need. However, there are situations where XPath is a better fit—particularly when I need to navigate through an element's hierarchy, such as moving from an element to its parent, grandparent, or sibling. This post shows one such real-world example. The Problem I came across a situation where I needed to click a link based on the value of an input field. The HTML structure contained multiple similar groups of elements. The input field and the link I wanted to click were not directly related, but they shared a common parent structure. In the following example above, the input element is highlighted, and I need to click the corresponding anchor ( <a> ) element . The challenge is that there may be multiple similar structures on the page. I th...
Read more