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Procfs: Difference between revisions
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==proc/PID== | ==proc/PID== | ||
Each entity associated with a non-zero PID (this includes most kernel threads) has a corresponding toplevel procfs directory named by its PID (e.g. when using [[systemd]] as init and mounting procfs at | Each entity associated with a non-zero PID (this includes most kernel threads) has a corresponding toplevel procfs directory named by its PID (e.g. when using [[systemd]] as init and mounting procfs at <tt>/proc</tt>, systemd's primary process is described by <tt>/proc/1</tt> (the process only appears in procfs mounts within the same PID namespace). One of the entries is <tt>proc/PID/task</tt>, a directory which contains the threads making up the process, using the TID as name: | ||
<pre> | <pre> | ||
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</pre> | </pre> | ||
procfs since Linux 3.3 accepts a mount option | procfs since Linux 3.3 accepts a mount option <tt>hidepid</tt>, taking one of three values: | ||
* 0: everyone may access all | * 0: everyone may access all <tt>proc/PID` directories | ||
* 1: users can only access their own | * 1: users can only access their own <tt>proc/PID</tt> directories | ||
* 2: users can only *see* their own | * 2: users can only *see* their own <tt>proc/PID</tt> directories | ||
Linux 3.3 also introduced the | Linux 3.3 also introduced the <tt>gid</tt> parameter, which specifies a group ID. Members of this group are exempted from <tt>hidepid</tt> restrictions. | ||
===proc/PID/stat sucks=== | ===proc/PID/stat sucks=== | ||
<tt>/proc/PID/stat</tt> | |||
==See Also== | ==See Also== | ||
* The [[sysfs]] page | * The [[sysfs]] page | ||
