Author Archives: jeffrin

kernel space and user space

Kernel space. Linux (which is a kernel) manages the machine’s hardware in a simple and efficient manner, offering the user a simple and uniform programming interface. In the same way, the kernel, and in particular its device drivers, form a bridge or interface between the end-user/programmer and the hardware. Any subroutines or functions forming part …

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irb interactive ruby and ruby files

commandline session $ 4.2.20 9 508—> irb irb(main):001:0> 10+10 => 20 irb(main):002:0> 34*5 => 170 irb(main):003:0> 9-8 => 1 irb(main):004:0> () => nil irb(main):005:0> $ 4.2.20 12 511—> ruby sum.rb 3 $ 4.2.20 13 512—> cat sum.rb a = 1 + 2 puts a $ 4.2.20 14 513—> $ 4.2.20 15 514—> irb irb(main):001:0> Dir.entries(‘/home/jeffrin/shelter/symmel/’) …

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kernel sources and RE with cut and head

commandline session $ 4.2.20 26 526—> time grep -r ‘^Linus’ * | head -n20 | cut -c 1-31 arch/x86/math-emu/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus debian/pkg/headers/README:Linus real 0m1.110s user 0m0.444s sys 0m0.608s $ 4.2.20 27 527—>

using regular expressions in kernel source

commandline session $ 4.2.20 67 568—> grep -r ‘^kernel’ * | head -n20 arch/alpha/kernel/entry.S:kernel_thread: arch/alpha/kernel/entry.S:kernel_execve: arch/avr32/kernel/head.S:kernel_entry: arch/avr32/kernel/head.S:kernel_start_addr: arch/sh/boot/compressed/head_32.S:kernel_start_addr: arch/mn10300/kernel/kernel_execve.S:kernel_execve: arch/mn10300/kernel/kthread.S:kernel_thread_helper: arch/um/.gitignore:kernel/config.c arch/um/.gitignore:kernel/config.tmp arch/um/.gitignore:kernel/vmlinux.lds arch/cris/arch-v32/kernel/process.c:kernel_thread_helper(void* dummy, int (*fn)(void *), void * arg) arch/cris/arch-v32/kernel/process.c:kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) arch/cris/arch-v32/kernel/entry.S:kernel_execve: arch/cris/include/arch-v32/arch/bitops.h:kernel_ffs(unsigned long w) arch/cris/arch-v10/kernel/entry.S:kernel_execve: arch/cris/arch-v10/README.mm:kernel segments like the i386, need to setup swapper_pg_dir directly …

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send patches using git using yahoo mail server

ABOUT git Git (/ɡɪt/[7]) is a distributed version control system for tracking changes in source code during software development.[8] It is designed for coordinating work among programmers, but it can be used to track changes in any set of files. Its goals include speed,[9] data integrity,[10] and support for distributed, non-linear workflows. MAY BE CORRECT …

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&~ operation in C

commandline session switch (_NSIG_WORDS) { default: for (i = _NSIG_WORDS, ready = 0; –i >= 0 ; ) ready |= signal->sig[i] &~ blocked->sig[i]; break; case 4: ready = signal->sig[3] &~ blocked->sig[3]; ready |= signal->sig[2] &~ blocked->sig[2]; ready |= signal->sig[1] &~ blocked->sig[1]; ready |= signal->sig[0] &~ blocked->sig[0]; break; case 2: ready = signal->sig[1] &~ blocked->sig[1]; ready …

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(java) bubble sort testing… 0.00003 Ver — 27 No.’s Related

$ 4.2.20 5 505—> time java BubbleSort real 0m0.247s user 0m0.172s sys 0m0.052s $ 4.2.20 6 506—> time java BubbleSort real 0m0.204s user 0m0.148s sys 0m0.036s $ 4.2.20 7 507—> time java BubbleSort real 0m0.207s user 0m0.152s sys 0m0.032s $ 4.2.20 8 508—> time java BubbleSort real 0m0.222s user 0m0.168s sys 0m0.032s $ 4.2.20 9 …

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