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来自「linux 0.11中文版 有注释」· HTML 代码 · 共 370 行 · 第 1/3 页

<a name='L112'><i><font color='green'>// unsigned short suid 保存的用户id。</font></i>
<a name='L113'><i><font color='green'>// unsigned short gid 组标识号（组id）。</font></i>
<a name='L114'><i><font color='green'>// unsigned short egid 有效组id。</font></i>
<a name='L115'><i><font color='green'>// unsigned short sgid 保存的组id。</font></i>
<a name='L116'><i><font color='green'>// long alarm 报警定时值（滴答数）。</font></i>
<a name='L117'><i><font color='green'>// long utime 用户态运行时间（滴答数）。</font></i>
<a name='L118'><i><font color='green'>// long stime 系统态运行时间（滴答数）。</font></i>
<a name='L119'><i><font color='green'>// long cutime 子进程用户态运行时间。</font></i>
<a name='L120'><i><font color='green'>// long cstime 子进程系统态运行时间。</font></i>
<a name='L121'><i><font color='green'>// long start_time 进程开始运行时刻。</font></i>
<a name='L122'><i><font color='green'>// unsigned short used_math 标志：是否使用了协处理器。</font></i>
<a name='L123'><i><font color='green'>// --------------------------</font></i>
<a name='L124'><i><font color='green'>// int tty 进程使用tty 的子设备号。-1 表示没有使用。</font></i>
<a name='L125'><i><font color='green'>// unsigned short umask 文件创建属性屏蔽位。</font></i>
<a name='L126'><i><font color='green'>// struct m_inode * pwd 当前工作目录i 节点结构。</font></i>
<a name='L127'><i><font color='green'>// struct m_inode * root 根目录i 节点结构。</font></i>
<a name='L128'><i><font color='green'>// struct m_inode * executable 执行文件i 节点结构。</font></i>
<a name='L129'><i><font color='green'>// unsigned long close_on_exec 执行时关闭文件句柄位图标志。（参见include/fcntl.h）</font></i>
<a name='L130'><i><font color='green'>// struct file * filp[NR_OPEN] 进程使用的文件表结构。</font></i>
<a name='L131'><i><font color='green'>// --------------------------</font></i>
<a name='L132'><i><font color='green'>// struct desc_struct ldt[3] 本任务的局部表描述符。0-空，1-代码段cs，2-数据和堆栈段ds&amp;ss。</font></i>
<a name='L133'><i><font color='green'>// --------------------------</font></i>
<a name='L134'><i><font color='green'>// struct tss_struct tss 本进程的任务状态段信息结构。</font></i>
<a name='L135'><i><font color='green'>// ==========================</font></i>
<a name='L136'><b>struct</b> task_struct
<a name='L137'><font color='red'>{</font>
<a name='L138'><i><font color='green'>/* these are hardcoded - don't touch */</font></i>
<a name='L139'>  <b>long</b> state;                   <i><font color='green'>/* -1 unrunnable, 0 runnable, &gt;0 stopped */</font></i>
<a name='L140'>  <b>long</b> counter;
<a name='L141'>  <b>long</b> priority;
<a name='L142'>  <b>long</b> signal;
<a name='L143'>  <b>struct</b> sigaction sigaction[32];
<a name='L144'>  <b>long</b> blocked;                 <i><font color='green'>/* bitmap of masked signals */</font></i>
<a name='L145'><i><font color='green'>/* various fields */</font></i>
<a name='L146'>  <b>int</b> exit_code;
<a name='L147'>  <b>unsigned</b> <b>long</b> start_code, end_code, end_data, brk, start_stack;
<a name='L148'>  <b>long</b> pid, father, pgrp, session, leader;
<a name='L149'>  <b>unsigned</b> <b>short</b> uid, euid, suid;
<a name='L150'>  <b>unsigned</b> <b>short</b> gid, egid, sgid;
<a name='L151'>  <b>long</b> alarm;
<a name='L152'>  <b>long</b> utime, stime, cutime, cstime, start_time;
<a name='L153'>  <b>unsigned</b> <b>short</b> used_math;
<a name='L154'><i><font color='green'>/* file system info */</font></i>
<a name='L155'>  <b>int</b> <a href='../S/7.html#L44' title='Defined at 44 in fs/char_dev.c.'>tty</a>;                      <i><font color='green'>/* -1 if no tty, so it must be signed */</font></i>
<a name='L156'>  <b>unsigned</b> <b>short</b> umask;
<a name='L157'>  <b>struct</b> m_inode *pwd;
<a name='L158'>  <b>struct</b> m_inode *root;
<a name='L159'>  <b>struct</b> m_inode *executable;
<a name='L160'>  <b>unsigned</b> <b>long</b> close_on_exec;
<a name='L161'>  <b>struct</b> file *filp[<a href='../S/31.html#L59' title='Defined at 59 in include/linux/fs.h.'>NR_OPEN</a>];
<a name='L162'><i><font color='green'>/* ldt for this task 0 - zero 1 - cs 2 - ds&amp;ss */</font></i>
<a name='L163'>  <b>struct</b> desc_struct ldt[3];
<a name='L164'><i><font color='green'>/* tss for this task */</font></i>
<a name='L165'>  <b>struct</b> tss_struct tss;
<a name='L166'><font color='red'>}</font>;
<a name='L167'>
<a name='L168'><i><font color='green'>/*</font></i>
<a name='L169'><i><font color='green'>* INIT_TASK is used to set up the first task table, touch at</font></i>
<a name='L170'><i><font color='green'>* your own risk!. Base=0, limit=0x9ffff (=640kB)</font></i>
<a name='L171'><i><font color='green'>*/</font></i>
<a name='L172'><i><font color='green'>/*</font></i>
<a name='L173'><i><font color='green'>* INIT_TASK 用于设置第1 个任务表，若想修改，责任自负?！</font></i>
<a name='L174'><i><font color='green'>* 基址Base = 0，段长limit = 0x9ffff（=640kB）。</font></i>
<a name='L175'><i><font color='green'>*/</font></i>
<a name='L176'><i><font color='green'>// 对应上面任务结构的第1 个任务的信息。</font></i>
<a name='L177'><font color='darkred'>#define</font> <a href='../S/74.html#L72' title='Refered from 72 in kernel/sched.c.'>INIT_TASK</a> \
<a name='L178'><i><font color='green'>/* state etc */</font></i> <font color='red'>{</font> 0,15,15, \    <i><font color='green'>// state, counter, priority</font></i>
<a name='L179'><i><font color='green'>/* signals */</font></i> 0,
<a name='L180'><font color='red'>{</font>
<a name='L181'>  <font color='red'>{</font>
<a name='L182'>  <font color='red'>}</font>
<a name='L183'>,<font color='red'>}</font>
<a name='L184'>
<a name='L185'>, 0, \                          <i><font color='green'>// signal, sigaction[32], blocked</font></i>
<a name='L186'>                                        <i><font color='green'>/* ec,brk... */</font></i> 0, 0, 0, 0, 0, 0, \
<a name='L187'>                                        <i><font color='green'>// exit_code,start_code,end_code,end_data,brk,start_stack</font></i>
<a name='L188'>                                        <i><font color='green'>/* pid etc.. */</font></i> 0, -1, 0, 0, 0, \
<a name='L189'>                                        <i><font color='green'>// pid, father, pgrp, session, leader</font></i>
<a name='L190'>                                        <i><font color='green'>/* uid etc */</font></i> 0, 0, 0, 0, 0, 0, \
<a name='L191'>                                        <i><font color='green'>// uid, euid, suid, gid, egid, sgid</font></i>
<a name='L192'>                                        <i><font color='green'>/* alarm */</font></i> 0, 0, 0, 0, 0, 0, \
<a name='L193'>                                        <i><font color='green'>// alarm, utime, stime, cutime, cstime, start_time</font></i>
<a name='L194'>                                <i><font color='green'>/* math */</font></i> 0, \
<a name='L195'>                                <i><font color='green'>// used_math</font></i>
<a name='L196'>                                                        <i><font color='green'>/* fs info */</font></i> -1, 0022, <a href='../D/261.html' title='Multiple defined in 12 places.'>NULL</a>, <a href='../D/261.html' title='Multiple defined in 12 places.'>NULL</a>, <a href='../D/261.html' title='Multiple defined in 12 places.'>NULL</a>, 0, \
<a name='L197'>                                                        <i><font color='green'>// tty,umask,pwd,root,executable,close_on_exec</font></i>
<a name='L198'><i><font color='green'>/* filp */</font></i>
<a name='L199'><font color='red'>{</font>
<a name='L200'><a href='../D/261.html' title='Multiple defined in 12 places.'>NULL</a>,<font color='red'>}</font>
<a name='L201'>
<a name='L202'>, \                             <i><font color='green'>// filp[20]</font></i>
<a name='L203'><font color='red'>{</font>
<a name='L204'>  \                             <i><font color='green'>// ldt[3]</font></i>
<a name='L205'>  <font color='red'>{</font>
<a name='L206'>  0, 0<font color='red'>}</font>
<a name='L207'>  ,
<a name='L208'><i><font color='green'>/* ldt */</font></i>
<a name='L209'>  <font color='red'>{</font>
<a name='L210'>  0x9f, 0xc0fa00<font color='red'>}</font>
<a name='L211'>  , \                           <i><font color='green'>// 代码长640K，基址0x0，G=1，D=1，DPL=3，P=1 TYPE=0x0a</font></i>
<a name='L212'>  <font color='red'>{</font>
<a name='L213'>  0x9f, 0xc0f200<font color='red'>}</font>
<a name='L214'>  , \                           <i><font color='green'>// 数据长640K，基址0x0，G=1，D=1，DPL=3，P=1 TYPE=0x02</font></i>
<a name='L215'><font color='red'>}</font>
<a name='L216'>
<a name='L217'>,
<a name='L218'><i><font color='green'>/*tss*/</font></i>
<a name='L219'><font color='red'>{</font>
<a name='L220'>  0, <a href='../D/324.html' title='Multiple defined in 4 places.'>PAGE_SIZE</a> + (<b>long</b>) &amp;init_task, 0x10, 0, 0, 0, 0, (<b>long</b>) &amp;pg_dir, \ <i><font color='green'>// tss</font></i>
<a name='L221'>    0, 0, 0, 0, 0, 0, 0, 0,
<a name='L222'>    0, 0, 0x17, 0x17, 0x17, 0x17, 0x17, 0x17, <a href='../S/36.html#L260' title='Defined at 260 in include/linux/sched.h.'>_LDT</a> (0), 0x80000000,
<a name='L223'>  <font color='red'>{</font>
<a name='L224'>  <font color='red'>}</font>
<a name='L225'><font color='red'>}</font>
<a name='L226'>,<font color='red'>}</font>
<a name='L227'>
<a name='L228'><b>extern</b> <b>struct</b> task_struct *task[<a href='../S/36.html#L4' title='Defined at 4 in include/linux/sched.h.'>NR_TASKS</a>];      <i><font color='green'>// 任务数组。</font></i>
<a name='L229'><b>extern</b> <b>struct</b> task_struct *last_task_used_math; <i><font color='green'>// 上一个使用过协处理器的进程。</font></i>
<a name='L230'><b>extern</b> <b>struct</b> task_struct *current;     <i><font color='green'>// 当前进程结构指针变量。</font></i>
<a name='L231'><b>extern</b> <b>long</b> <b>volatile</b> jiffies;   <i><font color='green'>// 从开机开始算起的滴答数（10ms/滴答）。</font></i>
<a name='L232'><b>extern</b> <b>long</b> startup_time;       <i><font color='green'>// 开机时间。从1970:0:0:0 开始计时的秒数。</font></i>
<a name='L233'>
<a name='L234'><font color='darkred'>#define</font> <a href='../R/21.html' title='Multiple refered from 19 places.'>CURRENT_TIME</a> (startup_time+jiffies/<a href='../S/36.html#L5' title='Defined at 5 in include/linux/sched.h.'>HZ</a>)  <i><font color='green'>// 当前时间（秒数）。</font></i>
<a name='L235'>