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vidcontrol se gaseste in sistemele BSD , poate fi gasit si in Kfreebsd O alternativa: cat /dev/vcs1 > tty1 && less tty1 vcs1=tty1 vcs2=tty2 vcs3=tty3 vcs4=tty4 vcs5=tty5 vcs6=tty6 vcs7=tty7 Si inca una care de fapt merge pe acelasi principiu sudo setterm -dump 1 && less screen.dump Unde 1 este numarul de la primul tty

Generare de parole sigure din CLI: tr -dc A-Za-z0-9_ < /dev/urandom | head -c 20 | xargs openssl rand -base64 12 openssl rand -base64 37 | cut -c1-37 openssl rand -base64 37 | sed -e 's/^\(.\{37\}\).*/\1/g' openssl rand -base64 37 | awk 'BEGIN{FS=""} {for (i=1;i<=37;i++) printf("%s",$i);} {printf "\n"}'

O parte din programatori nu scriu cod eficient fie ca habar nu au ca scriu prost (asta e si vina IDE-ului care compileaza direct cu -O3) fie ca stiu ca oricum compilatorul le repara prostiile. De curand am avut de facut un proiect si nu aveam voie sa folosesc flagurile -O1, -O2, -O3 la compilare. Linkurile de mai jos mi-au folosit. Optimizing C and C++ Code Adjust structure sizes to power of two Place case labels in narrow range Place frequent case labels first Break big switch statements into nested switches Minimize local variables Declare local variables in the inner most scope Reduce the number of parameters Use references for parameter passing and return value for types bigger than 4 bytes Don't define a return value if not used Consider locality of reference for code and data Prefer int over char and short Define lightweight constructors Prefer initialization over assignment Use constructor initialization lists Do not declare "just in case" virtual functions In-line 1 to 3 line functions C++ Optimization Strategies and Techniques General Strategies There's a right way and a wrong way to do optimization. Here's some strategies common to all programming endeavors that work and don't work. Optimization Strategies that Bomb Optimization Strategies that Work Example of Selecting the Proper Algorithm C++ Design Considerations When you start working on your next app and begin to think about coding conventions, compilers, libraries, and general C++ issues, there are many factors to consider. In this section I weigh performance issues involved with C++ design considerations. Take advantage of STL containers Consider using references instead of pointers Consider two-phase construction Limit exception handling Avoid Runtime Type Identification Prefer stdio to iostream Evaluate alternative libraries C++ Optimizations You Can Do "As You Go" Defy the software engineering mantra of "optimization procrastination." These techniques can be added to your code today! In general, these methods not only make your code more efficient, but increase readability and maintainability, too. Pass class parameters by reference Postpone variable declaration as long as possible Prefer initialization over assignment Use constructor initialization lists Prefer operator= over operator alone Use prefix operators Use explicit constructors Final Optimizations Your app is up and running. The data structures are ideal, the algorithms sublime, the code elegant, but the program - well, it's not quite living up to its potential. Time to get drastic, and with drastic measures, there are tradeoffs to consider. These optimizations are going to make your code less modular, harder to understand, and more difficult to maintain. They may cause unexpected side effects like code bloat. Your compiler may not even be able to handle some of the more advanced template-based techniques. Proceed with caution. Arm yourself with a good profiler. Inline functions Avoid temporary objects: the return value optimization Be aware of the cost of virtual functions Return objects via reference parameters Consider per-class allocation Consider STL container allocators The "empty member" optimization Template metaprogramming Copy on write Compiler Optimizations A good compiler can have a huge effect on code performance. Most PC compilers are good, but not great, at optimization. Be aware that sometimes the compiler won't perform optimizations even though it can. The compiler assigns a higher priority to producing consistent and correct code than optimizing performance. Be thankful for small favors. C language settings C++ language settings The "ultimate" compiler settings Use the novtable option for abstract classes (Microsoft Visual C++) Indicate functions that don't throw exceptions Use the fastcall calling convention (Microsoft Visual C++) Warning: Unsafe optimizations Appendices STL Container efficiency table Relative costs of common programming operations C code tuning and C++ efficiency resources The Author