рпм = русскоязычный пакетный менеджер

Как линукс запускает бинарники?

• fs/exec.c defines the system call at SYSCALL_DEFINE3(execve

  Simply forwards to do_execve.

• do_execve

  Forwards to do_execveat_common.

• do_execveat_common

  To find the next major function, track when return value retval is last modified.

  Starts building a struct linux_binprm *bprm to describe the program, and passes it to exec_binprm to execute.

• exec_binprm

  Once again, follow the return value to find the next major call.

• search_binary_handler

  • Handlers are determined by the first magic bytes of the executable.

    The two most common handlers are those for interpreted files (#! magic) and for ELF (\x7fELF magic), but there are other built-into the kernel, e.g. a.out. And users can also register their own though /proc/sys/fs/binfmt_misc

    The ELF handler is defined at fs/binfmt_elf.c.

  • The formats list contains all the handlers.

    Each handler file contains something like:

    static int __init init_elf_binfmt(void)
    {
        register_binfmt(&elf_format);
        return 0;
    }

    and elf_format is a struct linux_binfmt defined in that file.

    __init is magic and puts that code into a magic section that gets called when the kernel starts: What does __init mean in the Linux kernel code?

    Linker-level dependency injection!

  • There is also a recursion counter, in case an interpreter executes itself infinitely.

    Try this:

    echo '#!/tmp/a' > /tmp/a
    chmod +x /tmp/a
    /tmp/a

  • Once again we follow the return value to see what comes next, and see that it comes from:

    retval = fmt->load_binary(bprm);

    where load_binary is defined for each handler on the struct: C-style polymorsphism.

• fs/binfmt_elf.c:load_binary

  Does the actual work:

  • parses the ELF file according to the specs
  • sets up the process initial program state based on the parsed ELF (memory into a struct linux_binprm, registers into a struct pt_regs)
  • call start_thread, which is where it can really start to getting scheduled

  TODO: enter into more detail here. In particular, what RIP gets set to and how the dynamic loader is started.

Кодировка названий в файловой системе

разделитель директорий

Как запускается bash?

# eix -cC app-shells
[N] app-shells/autojump (--): change directory command that learns
[?] app-shells/bash (4.3_p42-r1@01/14/2016 -> 4.3_p39): The standard GNU Bourne again shell
[?] app-shells/bash-completion (2.3-r2@04/28/2016 -> 2.1_p20141224): Programmable Completion for bash
[N] app-shells/bashdb (--): bash source code debugging
[N] app-shells/bashish (2.2.4): Text console theme engine
[N] app-shells/ccsh (0.0.4-r3): UNIX Shell for people already familiar with the C language
[N] app-shells/dash (0.5.8.2): DASH is a direct descendant of the NetBSD version of ash (the Almquist SHell) and is POSIX compliant
[N] app-shells/dsh (0.25.10): Distributed Shell
[N] app-shells/esh (0.8.5-r2): A UNIX Shell with a simplified Scheme syntax
[N] app-shells/fish ((~)2.2.0): fish is the Friendly Interactive SHell
[I] app-shells/gentoo-bashcomp (20140911@11/24/2014): Gentoo-specific bash command-line completions (emerge, ebuild, equery, repoman, layman, etc)
[N] app-shells/gentoo-zsh-completions ((~)20150103): Gentoo specific zsh completion support (includes emerge and ebuild commands)
[N] app-shells/heirloom-sh ((~)050706): Heirloom Bourne Shell, derived from OpenSolaris code SVR4/SVID3
[N] app-shells/ksh ((~)93.20140625): The Original Korn Shell, 1993 revision (ksh93)
[N] app-shells/localshell (1.3.4): Localshell allows per-user/group local control of shell execution
[N] app-shells/mksh ((~)51): MirBSD Korn Shell
[N] app-shells/mpibash ((~)1.2): Parallel scripting right from the Bourne-Again Shell (Bash)
[N] app-shells/pdmenu ((~)1.3.4): A simple console menu program
[N] app-shells/pdsh ((~)2.26): A high-performance, parallel remote shell utility
[N] app-shells/posh ((~)0.12): Reimplementation of Bourne shell based on pdksh
[N] app-shells/psh (1.8.1-r1): Combines the interactive nature of a Unix shell with the power of Perl
[I] app-shells/push (1.6@06/27/2015): A POSIX shell function to treat a variable like an array, quoting args
[N] app-shells/rc ((~)1.7.2): A reimplementation of the Plan 9 shell
[N] app-shells/rrs (1.70-r1): Reverse Remote Shell
[N] app-shells/rssh ((~)2.3.4_p3): Restricted shell for SSHd
[N] app-shells/rust-zshcomp ((~)1_beta20150411): Rust zsh completions
[N] app-shells/sash (3.8): A small (static) UNIX Shell
[N] app-shells/scsh ((~)0.6.7-r1): Unix shell embedded in Scheme
[N] app-shells/scsh-install-lib (--): Installation tool for the Scheme Untergrund Library
[N] app-shells/shish (--): The diet shell
[N] app-shells/smrsh ((~)8.14.9): Sendmail restricted shell, for use with MTAs other than Sendmail
[N] app-shells/soapbox ((~)0.3.1-r1): A preload (sandbox) library to restrict filesystem writes
[N] app-shells/squirrelsh ((~)1.2.7): An advanced, cross-platform object oriented scripting shell based on the squirrel scripting language
[N] app-shells/tcsh ((~)6.18.01-r3): Enhanced version of the Berkeley C shell (csh)
[N] app-shells/zsh ((~)5.0.8): UNIX Shell similar to the Korn shell
[N] app-shells/zsh-completions ((~)0.12.0-r2): Additional completion definitions for Zsh
Found 36 matches.

команды русскими буквами

Параметры команд русскими буквами