* More doc updates.
This commit is contained in:
Eelco Dolstra
parent
7d876f8fa7
commit
b9d8ecbc6a
|
|
@ -1,54 +1,69 @@
|
|||
<refentry>
|
||||
<refnamediv>
|
||||
<refname>nix-prefetch-url</refname>
|
||||
<refpurpose>copy a file from a URL into the store and print its MD5 hash</refpurpose>
|
||||
</refnamediv>
|
||||
|
||||
<refnamediv>
|
||||
<refname>nix-prefetch-url</refname>
|
||||
<refpurpose>copy a file from a URL into the store and print its MD5 hash</refpurpose>
|
||||
</refnamediv>
|
||||
|
||||
<refsynopsisdiv>
|
||||
<cmdsynopsis>
|
||||
<command>nix-prefetch-url</command>
|
||||
<arg choice='plain'><replaceable>url</replaceable></arg>
|
||||
</cmdsynopsis>
|
||||
</refsynopsisdiv>
|
||||
<refsynopsisdiv>
|
||||
<cmdsynopsis>
|
||||
<command>nix-prefetch-url</command>
|
||||
<arg choice='plain'><replaceable>url</replaceable></arg>
|
||||
<arg><replaceable>hash</replaceable></arg>
|
||||
</cmdsynopsis>
|
||||
</refsynopsisdiv>
|
||||
|
||||
<refsection>
|
||||
<title>Description</title>
|
||||
|
||||
<para>
|
||||
The command <command>nix-prefetch-url</command> downloads the
|
||||
file referenced by the URL <replaceable>url</replaceable>,
|
||||
prints its MD5 cryptographic hash code, and copies it into the
|
||||
Nix store. The file name in the store is
|
||||
<filename><replaceable>hash</replaceable>-<replaceable>basename</replaceable></filename>,
|
||||
where <replaceable>basename</replaceable> is everything
|
||||
following the final slash in <replaceable>url</replaceable>.
|
||||
</para>
|
||||
<refsection><title>Description</title>
|
||||
|
||||
<para>
|
||||
This command is just a convenience to Nix expression writers.
|
||||
Often a Nix expressions fetch some source distribution from the
|
||||
network using the <literal>fetchurl</literal> expression
|
||||
contained in <literal>nixpkgs</literal>. However,
|
||||
<literal>fetchurl</literal> requires an MD5 hash. If you don't
|
||||
know the hash, you would have to download the file first, and
|
||||
then <literal>fetchurl</literal> would download it again when
|
||||
you build your Nix expression. Since
|
||||
<literal>fetchurl</literal> uses the same name for the
|
||||
downloaded file as <command>nix-prefetch-url</command>, the
|
||||
redundant download can be avoided.
|
||||
</para>
|
||||
<para>The command <command>nix-prefetch-url</command> downloads the
|
||||
file referenced by the URL <replaceable>url</replaceable>, prints its
|
||||
cryptographic hash, and copies it into the Nix store. The file name
|
||||
in the store is
|
||||
<filename><replaceable>hash</replaceable>-<replaceable>baseName</replaceable></filename>,
|
||||
where <replaceable>baseName</replaceable> is everything following the
|
||||
final slash in <replaceable>url</replaceable>.</para>
|
||||
|
||||
</refsection>
|
||||
<para>This command is just a convenience for Nix expression writers.
|
||||
Often a Nix expression fetches some source distribution from the
|
||||
network using the <literal>fetchurl</literal> expression contained in
|
||||
Nixpkgs. However, <literal>fetchurl</literal> requires a
|
||||
cryptographic hash. If you don't know the hash, you would have to
|
||||
download the file first, and then <literal>fetchurl</literal> would
|
||||
download it again when you build your Nix expression. Since
|
||||
<literal>fetchurl</literal> uses the same name for the downloaded file
|
||||
as <command>nix-prefetch-url</command>, the redundant download can be
|
||||
avoided.</para>
|
||||
|
||||
<refsection>
|
||||
<title>Examples</title>
|
||||
<para>The environment variable <envar>NIX_HASH_ALGO</envar> specifies
|
||||
which hash algorithm to use. It can be either <literal>md5</literal>,
|
||||
<literal>sha1</literal>, or <literal>sha256</literal>. The default is
|
||||
<literal>md5</literal>.</para>
|
||||
|
||||
<screen>
|
||||
<para>If <replaceable>hash</replaceable> is specified, then a download
|
||||
is not performed if the Nix store already contains a file with the
|
||||
same hash and base name. Otherwise, the file is downloaded, and an
|
||||
error if signaled if the actual hash of the file does not match the
|
||||
specified hash.</para>
|
||||
|
||||
<para>This command prints the hash on standard output. Additionally,
|
||||
if the environment variable <envar>PRINT_PATH</envar> is set, the path
|
||||
of the downloaded file in the Nix store is also printed.</para>
|
||||
|
||||
</refsection>
|
||||
|
||||
|
||||
<refsection><title>Examples</title>
|
||||
|
||||
<screen>
|
||||
$ nix-prefetch-url ftp://ftp.nluug.nl/pub/gnu/make/make-3.80.tar.bz2
|
||||
...
|
||||
file has hash 0bbd1df101bc0294d440471e50feca71
|
||||
...</screen>
|
||||
0bbd1df101bc0294d440471e50feca71
|
||||
|
||||
$ PRINT_PATH=1 nix-prefetch-url ftp://ftp.nluug.nl/pub/gnu/make/make-3.80.tar.bz2
|
||||
0bbd1df101bc0294d440471e50feca71
|
||||
/nix/store/wvyz8ifdn7wyz1p3pqyn0ra45ka2l492-make-3.80.tar.bz2</screen>
|
||||
|
||||
</refsection>
|
||||
|
||||
</refsection>
|
||||
|
||||
</refentry>
|
||||
|
|
|
|||
|
|
@ -189,7 +189,7 @@ linkend="sec-nix-build"><command>nix-build</command></link> does.</para>
|
|||
<cmdsynopsis>
|
||||
<command>nix-store</command>
|
||||
<arg choice='plain'><option>--gc</option></arg>
|
||||
<group choice='req'>
|
||||
<group>
|
||||
<arg choice='plain'><option>--print-roots</option></arg>
|
||||
<arg choice='plain'><option>--print-live</option></arg>
|
||||
<arg choice='plain'><option>--print-dead</option></arg>
|
||||
|
|
@ -451,7 +451,7 @@ most one query can be specified. The default query is
|
|||
|
||||
<cmdsynopsis>
|
||||
<command>nix-store</command>
|
||||
<arg choice='req'><option>--register-validity</option></arg>
|
||||
<arg choice='plain'><option>--register-validity</option></arg>
|
||||
</cmdsynopsis>
|
||||
</refsection>
|
||||
|
||||
|
|
@ -473,7 +473,7 @@ most one query can be specified. The default query is
|
|||
|
||||
<cmdsynopsis>
|
||||
<command>nix-store</command>
|
||||
<arg choice='req'><option>--substitute</option></arg>
|
||||
<arg choice='plain'><option>--substitute</option></arg>
|
||||
<arg choice='plain'
|
||||
rep='repeat'><replaceable>srcpath</replaceable> <replaceable>subpath</replaceable></arg>
|
||||
</cmdsynopsis>
|
||||
|
|
@ -501,7 +501,8 @@ deployment.</para>
|
|||
<title>Synopsis</title>
|
||||
<cmdsynopsis>
|
||||
<command>nix-store</command>
|
||||
<arg choice='req'><option>--verify</option></arg>
|
||||
<arg choice='plain'><option>--verify</option></arg>
|
||||
<arg><option>--check-contents</option></arg>
|
||||
</cmdsynopsis>
|
||||
</refsection>
|
||||
|
||||
|
|
@ -514,6 +515,25 @@ automatically repaired. Inconsistencies are generally the result of
|
|||
the Nix store or database being modified by non-Nix tools, or of bugs
|
||||
in Nix itself.</para>
|
||||
|
||||
<para>There is one option:
|
||||
|
||||
<variablelist>
|
||||
|
||||
<varlistentry><term><option>--check-contents</option></term>
|
||||
|
||||
<listitem><para>Checks that the contents of every valid store path
|
||||
has not been altered by computing a SHA-256 hash of the contents
|
||||
and comparing it with the hash stored in the Nix database at build
|
||||
time. Paths that have been modified are printed out. For large
|
||||
stores, <option>--check-contents</option> is obviously quite
|
||||
slow.</para></listitem>
|
||||
|
||||
</varlistentry>
|
||||
|
||||
</variablelist>
|
||||
|
||||
</para>
|
||||
|
||||
</refsection>
|
||||
|
||||
</refsection>
|
||||
|
|
|
|||
Loading…
Reference in a new issue