Prevent file from being modified or deleted even by chattr
Make file in linux readonly
You can't see the question owner's special color Similar to pissing contest - but not in an aggressive manner. Just each guy attempting to out talk one another to show they are the leader / in charge.   Sample sentence:     Well, that meeting was more of a X than being productive with Greg trying to show he was in control. Vector spaces for the irreducible representations of the Lorentz Group Why is $l^\infty$ not separable? Prove that $\mathbb{Z}[\omega]$ is an integral domain What is the meaning of the integral of position? Jerk, $j(t)=\dddot x(t)$, acceleration, $a(t)=\ddot x(t)$ and velocity, $v(t)=\dot x(t)$ are derivatives of position, $x(t)$. What is the meaning of the integral of position?  For example, one could write  $$\int x \mathrm{d}t = \int x \frac{\mathrm{d}t}{\mathrm{d}x}\mathrm{d}x = \int x\frac{1}{v} \mathrm{d}x$$  which reminds the equation for . If a motherboard doesn't explicitly support a RAM frequency, is still compatible? For example, my  says this:   Supports DDR3 2133(OC)/1866(OC)/1600/1333/1066 non-ECC, un-buffered memory   Is RAM clocked at 2400 MHz compatible? Will the performance be downgraded or it just won't work?  I found other questions but they were related to the CPU cap at 1600 MHz. This cap is related to the motherboard, specs says 2133(OC) max. What's the proper way to typeset a differential operator? I can't seem to find any consensus on the right way to typeset a differential operator, whether it is:   in a standalone context:  as part of a derivative:  as part of an integral:    In all of these cases, I have seen them sometimes italicized like variables (as in the second and third examples above) and sometimes not italicized like operator names (as in the first example above). There is also additional variation in how much spacing goes between the "d" and whatever it is acting on.  Seeing as this is an incredibly common symbol in many branches of mathematics, I am curious about the lack of standardization -- I've seen all possible combinations used in all possible contexts by many respected authors and publishers.  Are there any rules of thumb that I can follow? I personally tend to prefer the non-italicized version with very little space next to it, so I add:  \renewcommand{\d}[1]{\ensuremath{\operatorname{d}\!{#1}}}   to my default preamble, and use that everywhere, but I'd like to know if I'm breaking any hard-and-fast rules here. "Above"/"below" before/after a noun postfix - how to prevent users from sending with another users name Even though my postfix server cannot be used without authentification (open relay), sending mail in another users name after logging in is still possible like this:  EHLO domain.org auth plain eW91IGxpdHRsZSBkaXJ0eSBiYXN0YXJkIDstKQ== 235 2.7.0 Authentication successful mail from: otheruser@domain.org 250 2.1.0 Ok rcpt to: recipient@otherdomain.org 250 2.1.5 Ok data 354 End data with &lt;CR&gt;&lt;LF&gt;.&lt;CR&gt;&lt;LF&gt; Please send me your account info. . 250 2.0.0 Ok: queued as D40692A61AA quit   How can this be prevented? How to connect to remote X-Server (logged in via ssh) When I'm logged on to another host (e.g via ssh), how do I connect to the XServer of that machine (same user is logged in and is running a desktop (gnome))?  You may ask way I wish to do that: There are commands that don't open an X-Window, e.g. xinput, xhost, etc.. and there are situations where you want to run them from remote. Duplication formula for gamma function Using the  for $\Gamma(x)$ and $\Gamma\Big(x + \frac12\Big)$, how can I prove the ? This is problem $10.7.3$ in the book , by Boros and Moll.  Any help is highly appreciated. Help! My party isn't challenged? While I've been running my campaign, I'm starting to get stumped. I am playing with a party of four, and we recently switched from 3.5 to Pathfinder, but the problem was the same in both situations.  No matter what I throw at the party, they seem to have no problems. Even if I put them up against something that is supposed to be 'Epic' or 'overwhelming' in terms of CR, they make out just fine. The one exception to this is when I had several encounters in one day that taxed them to near death. Usually I have about two encounters a day, but that day I had four encounters, with two of them being APL+1 and the other two being APL+2, and that was challenging. But other than that nothing seems to faze them!  How can I make the game more challenging without making it harder?  Just for reference, the party is fairly standard, and low level (level 4):   Wizard (tends to resort to mind-affecting spells, or grease if the creature is immune) Cleric (heals a lot, but always has spells / healing left over) Rogue (sneak attack, of course, which is more potent in Pathfinder) Fighter (gets enlarged and in-charge'd) How to find the real user home directory using python? Have a look at the following code:  \documentclass[letterpaper]{article} \usepackage{amsmath,amssymb} \begin{document}  $2-\frac{2}{1-\left(\frac{2}{2-\frac{2}{x^2}}\right)}$\quad  $2-\dfrac{2}{1-\left(\dfrac{2}{2-\dfrac{2}{x^2}}\right)}$\quad  $2-\cfrac{2}{1-\left(\cfrac{2}{2-\cfrac{2}{x^2}}\right)}$\quad  $2-\dfrac{2}{1-\left(\cfrac{2}{2-\dfrac{2}{x^2}}\right)}$ \end{document}   This gives:    Evidently, the first display is not the proper way. The second and last are the same I guess. The third has a better display but there is too much space above the 2 in \left(\cfrac{2}{2-\cfrac{2}{x^2}}\right). Essentially, non of the above displays satisfies, for me, a good Mathematical typsetting. Although, it may be argued that it is the default in LaTeX. I just can't get it right? Any insights? In a book I got this example from it looks like this without the excessive bold (this is a scanned image): Mrs Reed safe combination Mrs Reed forgets the number combination to her safe. The combination has $4$ numbers each is a $1$ digit number. The $4$ digits add up to $10$ and there are no zeros. How many times does Mrs Reed have to try to open her safe?  My attempt: ${9 \choose 3} = 84$ but the answer is $80$. Quantifiers "most" vs. "most of" Order of "not" with infinitive Is the collection of all functions between two sets a set? Are the tags shown in a particular order?