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diff --git a/static/freebsd/man5/fstab.5 3.html b/static/freebsd/man5/fstab.5 3.html new file mode 100644 index 00000000..d5f862a0 --- /dev/null +++ b/static/freebsd/man5/fstab.5 3.html @@ -0,0 +1,272 @@ +<table class="head"> + <tr> + <td class="head-ltitle">FSTAB(5)</td> + <td class="head-vol">File Formats Manual</td> + <td class="head-rtitle">FSTAB(5)</td> + </tr> +</table> +<div class="manual-text"> +<section class="Sh"> +<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> +<p class="Pp"><code class="Nm">fstab</code> — <span class="Nd">static + information about the file systems</span></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> +<p class="Pp"><code class="In">#include + <<a class="In">fstab.h</a>></code></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> +<p class="Pp">The file <code class="Nm">fstab</code> contains descriptive + information about the various file systems. <code class="Nm">fstab</code> is + only read by programs, and not written; it is the duty of the system + administrator to properly create and maintain this file. Each file system is + described on a separate line; fields on each line are separated by tabs or + spaces. The order of records in <code class="Nm">fstab</code> is important + because <a class="Xr">fsck(8)</a>, <a class="Xr">mount(8)</a>, and + <a class="Xr">umount(8)</a> sequentially iterate through + <code class="Nm">fstab</code> doing their thing.</p> +<p class="Pp">The first field, (<var class="Fa">fs_spec</var>), describes the + special device or remote file system to be mounted. The contents are decoded + by the <a class="Xr">strunvis(3)</a> function. This allows using spaces or + tabs in the device name which would be interpreted as field separators + otherwise.</p> +<p class="Pp">The second field, (<var class="Fa">fs_file</var>), describes the + mount point for the file system. For swap partitions, this field should be + specified as “none”. The contents are decoded by the + <a class="Xr">strunvis(3)</a> function, as above.</p> +<p class="Pp">The third field, (<var class="Fa">fs_vfstype</var>), describes the + type of the file system. The system can support various file system types. + Only the root, /usr, and /tmp file systems need be statically compiled into + the kernel; everything else will be automatically loaded at mount time. + (Exception: the FFS cannot currently be demand-loaded.) Some people still + prefer to statically compile other file systems as well.</p> +<p class="Pp">The fourth field, (<var class="Fa">fs_mntops</var>), describes the + mount options associated with the file system. It is formatted as a comma + separated list of options. It contains at least the type of mount (see + <var class="Fa">fs_type</var> below) plus any additional options appropriate + to the file system type. See the options flag (<code class="Fl">-o</code>) + in the <a class="Xr">mount(8)</a> page and the file system specific page, + such as <a class="Xr">mount_nfs(8)</a>, for additional options that may be + specified. All options that can be given to the file system specific mount + commands can be used in <code class="Nm">fstab</code> as well. They just + need to be formatted a bit differently. The arguments of the + <code class="Fl">-o</code> option can be used without the preceding + <code class="Fl">-o</code> flag. Other options need both the file system + specific flag and its argument, separated by an equal sign. For example, + mounting an <a class="Xr">msdosfs(4)</a> filesystem, the options</p> +<div class="Bd Pp Bd-indent Li"> +<pre>-o sync -o noatime -m 644 -M 755 -u foo -g bar</pre> +</div> +<p class="Pp">should be written as</p> +<div class="Bd Pp Bd-indent Li"> +<pre>sync,noatime,-m=644,-M=755,-u=foo,-g=bar</pre> +</div> +<p class="Pp">in the option field of <code class="Nm">fstab</code>.</p> +<p class="Pp">If the options “userquota” and/or + “groupquota” are specified, the file system is automatically + processed by the <a class="Xr">quotacheck(8)</a> command, and user and/or + group disk quotas are enabled with <a class="Xr">quotaon(8)</a>. By default, + file system quotas are maintained in files named + <span class="Pa">quota.user</span> and <span class="Pa">quota.group</span> + which are located at the root of the associated file system. These defaults + may be overridden by putting an equal sign and an alternative absolute + pathname following the quota option. Thus, if the user quota file for + <span class="Pa">/tmp</span> is stored in + <span class="Pa">/var/quotas/tmp.user</span>, this location can be specified + as:</p> +<div class="Bd Pp Bd-indent Li"> +<pre>userquota=/var/quotas/tmp.user</pre> +</div> +<p class="Pp">If the option “failok” is specified, the system will + ignore any error which happens during the mount of that filesystem, which + would otherwise cause the system to drop into single user mode. This option + is implemented by the <a class="Xr">mount(8)</a> command and will not be + passed to the kernel.</p> +<p class="Pp">If the option “noauto” is specified, the file system + will not be automatically mounted at system startup. Note that, for network + file systems of third party types (i.e., types supported by additional + software not included in the base system) to be automatically mounted at + system startup, the <var class="Va">extra_netfs_types</var> + <a class="Xr">rc.conf(5)</a> variable must be used to extend the + <a class="Xr">rc(8)</a> startup script's list of network file system + types.</p> +<p class="Pp">If the option “late” is specified, the file system + will be automatically mounted at a stage of system startup after remote + mount points are mounted. For more detail about this option, see the + <a class="Xr">mount(8)</a> manual page.</p> +<p class="Pp">If the option “update” is specified, it indicates + that the status of an already mounted file system should be changed + accordingly. This allows, for example, file systems mounted read-only to be + upgraded read-write and vice-versa. By default, an entry corresponding to a + file systems that is already mounted is going to be skipped over when + processing <code class="Nm">fstab</code>, unless it's a root file system, in + which case logic similar to “update” is applied + automatically.</p> +<p class="Pp">The “update” option is typically used in conjunction + with two <code class="Nm">fstab</code> files. The first + <code class="Nm">fstab</code> file is used to set up the initial set of file + systems. The second <code class="Nm">fstab</code> file is then run to update + the initial set of file systems and to add additional file systems.</p> +<p class="Pp">The type of the mount is extracted from the + <var class="Fa">fs_mntops</var> field and stored separately in the + <var class="Fa">fs_type</var> field (it is not deleted from the + <var class="Fa">fs_mntops</var> field). If <var class="Fa">fs_type</var> is + “rw” or “ro” then the file system whose name is + given in the <var class="Fa">fs_file</var> field is normally mounted + read-write or read-only on the specified special file.</p> +<p class="Pp">If <var class="Fa">fs_type</var> is “sw” then the + special file is made available as a piece of swap space by the + <a class="Xr">swapon(8)</a> command at the end of the system reboot + procedure. For swap devices, the keyword “trimonce” triggers + the delivery of a <code class="Dv">BIO_DELETE</code> command to the device. + This command marks the device's blocks as unused, except those that might + store a disk label. This marking can erase a crash dump. To delay + <code class="Nm">swapon</code> for a device until after + <code class="Nm">savecore</code> has copied the crash dump to another + location, use the “late” option. For vnode-backed swap spaces, + “file” is supported in the <var class="Fa">fs_mntops</var> + field. When <var class="Fa">fs_spec</var> is an <a class="Xr">md(4)</a> + device file (“md” or “md[0-9]*”) and + “file” is specified in <var class="Fa">fs_mntopts</var>, an + <a class="Xr">md(4)</a> device is created with the specified file used as + backing store, and then the new device is used as swap space. Swap entries + on <span class="Pa">.eli</span> devices will cause automatic creation of + encrypted devices. The “ealgo”, “aalgo”, + “keylen”, “notrim”, and + “sectorsize” options may be passed to control those + <a class="Xr">geli(8)</a> parameters. The fields other than + <var class="Fa">fs_spec</var> and <var class="Fa">fs_type</var> are unused. + If <var class="Fa">fs_type</var> is specified as “xx” the + entry is ignored. This is useful to show disk partitions which are currently + unused.</p> +<p class="Pp">The fifth field, (<var class="Fa">fs_freq</var>), is used for + these file systems by the <a class="Xr">dump(8)</a> command to determine + which file systems need to be dumped. If the fifth field is not present, a + value of zero is returned and <code class="Nm">dump</code> will assume that + the file system does not need to be dumped. If the fifth field is greater + than 0, then it specifies the number of days between dumps for this file + system.</p> +<p class="Pp">The sixth field, (<var class="Fa">fs_passno</var>), is used by the + <a class="Xr">fsck(8)</a> and <a class="Xr">quotacheck(8)</a> programs to + determine the order in which file system and quota checks are done at reboot + time. The <var class="Fa">fs_passno</var> field can be any value between 0 + and ‘<code class="Li">INT_MAX-1</code>’.</p> +<p class="Pp">The root file system should be specified with a + <var class="Fa">fs_passno</var> of 1, and other file systems should have a + <var class="Fa">fs_passno</var> of 2 or greater. A file system with a + <var class="Fa">fs_passno</var> value of 1 is always checked sequentially + and be completed before another file system is processed, and it will be + processed before all file systems with a larger + <var class="Fa">fs_passno</var>.</p> +<p class="Pp">For any given value of <var class="Fa">fs_passno</var>, file + systems within a drive will be checked sequentially, but file systems on + different drives will be checked at the same time to utilize parallelism + available in the hardware. Once all file system checks are complete for the + current <var class="Fa">fs_passno</var>, the same process will start over + for the next <var class="Fa">fs_passno</var>.</p> +<p class="Pp">If the sixth field is not present or is zero, a value of zero is + returned and <a class="Xr">fsck(8)</a> and <a class="Xr">quotacheck(8)</a> + will assume that the file system does not need to be checked.</p> +<p class="Pp">The <var class="Fa">fs_passno</var> field can be used to implement + finer control when the system utilities may determine that the file system + resides on a different physical device, when it actually does not, as with a + <a class="Xr">ccd(4)</a> device. All file systems with a lower + <var class="Fa">fs_passno</var> value will be completed before starting on + file systems with a higher <var class="Fa">fs_passno</var> value. E.g. all + file systems with a <var class="Fa">fs_passno</var> of 2 will be completed + before any file systems with a <var class="Fa">fs_passno</var> of 3 or + greater are started. Gaps are allowed between the different + <var class="Fa">fs_passno</var> values. E.g. file systems listed in + <span class="Pa">/etc/fstab</span> may have <var class="Fa">fs_passno</var> + values such as 0, 1, 2, 15, 100, 200, 300, and may appear in any order + within <span class="Pa">/etc/fstab</span>.</p> +<div class="Bd Pp Li"> +<pre>#define FSTAB_RW "rw" /* read/write device */ +#define FSTAB_RQ "rq" /* read/write with quotas */ +#define FSTAB_RO "ro" /* read-only device */ +#define FSTAB_SW "sw" /* swap device */ +#define FSTAB_XX "xx" /* ignore totally */ + +struct fstab { + char *fs_spec; /* block special device name */ + char *fs_file; /* file system path prefix */ + char *fs_vfstype; /* File system type, ufs, nfs */ + char *fs_mntops; /* Mount options ala -o */ + char *fs_type; /* FSTAB_* from fs_mntops */ + int fs_freq; /* dump frequency, in days */ + int fs_passno; /* pass number on parallel fsck */ +};</pre> +</div> +<p class="Pp">The proper way to read records from <span class="Pa">fstab</span> + is to use the routines <a class="Xr">getfsent(3)</a>, + <a class="Xr">getfsspec(3)</a>, <a class="Xr">getfstype(3)</a>, and + <a class="Xr">getfsfile(3)</a>.</p> +</section> +<section class="Sh"> +<h1 class="Sh" id="FILES"><a class="permalink" href="#FILES">FILES</a></h1> +<dl class="Bl-tag Bl-compact"> + <dt><span class="Pa">/etc/fstab</span></dt> + <dd>The file <code class="Nm">fstab</code> resides in + <span class="Pa">/etc</span>.</dd> +</dl> +</section> +<section class="Sh"> +<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> +<div class="Bd Li"> +<pre># Device Mountpoint FStype Options Dump Pass# +# +# UFS file system. +/dev/da0p2 / ufs rw 1 1 +# +# Swap space on a block device. +/dev/da0p1 none swap sw 0 0 +# +# Swap space using a block device with GELI encryption. +# aalgo, ealgo, keylen, sectorsize options are available +# for .eli devices. +/dev/da1p2.eli none swap sw 0 0 +# +# tmpfs. +tmpfs /tmp tmpfs rw,size=1g,mode=1777 0 0 +# +# UFS file system on a swap-backed md(4). /dev/md10 is +# automatically created. If it is "md", a unit number +# will be automatically selected. +md10 /scratch mfs rw,-s1g 0 0 +# +# Swap space on a vnode-backed md(4). +md11 none swap sw,file=/swapfile 0 0 +# +# CDROM. "noauto" option is typically used because the +# media is removable. +/dev/cd0 /cdrom cd9660 ro,noauto 0 0 +# +# NFS-exported file system. "serv" is an NFS server name +# or IP address. +serv:/export /nfs nfs rw,noinet6 0 0</pre> +</div> +</section> +<section class="Sh"> +<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE + ALSO</a></h1> +<p class="Pp"><a class="Xr">getfsent(3)</a>, <a class="Xr">getvfsbyname(3)</a>, + <a class="Xr">strunvis(3)</a>, <a class="Xr">ccd(4)</a>, + <a class="Xr">dump(8)</a>, <a class="Xr">fsck(8)</a>, + <a class="Xr">geli(8)</a>, <a class="Xr">mount(8)</a>, + <a class="Xr">quotacheck(8)</a>, <a class="Xr">quotaon(8)</a>, + <a class="Xr">swapon(8)</a>, <a class="Xr">umount(8)</a></p> +</section> +<section class="Sh"> +<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> +<p class="Pp">The <code class="Nm">fstab</code> file format appeared in + <span class="Ux">4.0BSD</span>.</p> +</section> +</div> +<table class="foot"> + <tr> + <td class="foot-date">April 14, 2014</td> + <td class="foot-os">FreeBSD 15.0</td> + </tr> +</table> |