diff options
Diffstat (limited to 'man/sd_id128_to_string.xml')
| -rw-r--r-- | man/sd_id128_to_string.xml | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/man/sd_id128_to_string.xml b/man/sd_id128_to_string.xml new file mode 100644 index 0000000..54cab1a --- /dev/null +++ b/man/sd_id128_to_string.xml @@ -0,0 +1,94 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> +<!-- SPDX-License-Identifier: LGPL-2.1-or-later --> + +<refentry id="sd_id128_to_string" xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_id128_to_string</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_id128_to_string</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_id128_to_string</refname> + <refname>sd_id128_from_string</refname> + <refpurpose>Format or parse 128-bit IDs as strings</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-id128.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>char *<function>sd_id128_to_string</function></funcdef> + <paramdef>sd_id128_t <parameter>id</parameter>, char <parameter>s</parameter>[33]</paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_id128_from_string</function></funcdef> + <paramdef>const char *<parameter>s</parameter>, sd_id128_t *<parameter>ret</parameter></paramdef> + </funcprototype> + + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_id128_to_string()</function> formats a 128-bit + ID as a character string. It expects the ID and a string array + capable of storing 33 characters. The ID will be formatted as 32 + lowercase hexadecimal digits and be terminated by a + <constant>NUL</constant> byte.</para> + + <para><function>sd_id128_from_string()</function> implements the reverse operation: it takes a 33 character string + with 32 hexadecimal digits (either lowercase or uppercase, terminated by <constant>NUL</constant>) and parses them + back into a 128-bit ID returned in <parameter>ret</parameter>. Alternatively, this call can also parse a + 37-character string with a 128-bit ID formatted as RFC UUID. If <parameter>ret</parameter> is passed as + <constant>NULL</constant> the function will validate the passed ID string, but not actually return it in parsed + form.</para> + + <para>For more information about the <literal>sd_id128_t</literal> + type see + <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>. + Note that these calls operate the same way on all architectures, + i.e. the results do not depend on endianness.</para> + + <para>When formatting a 128-bit ID into a string, it is often + easier to use a format string for + <citerefentry project='man-pages'><refentrytitle>printf</refentrytitle><manvolnum>3</manvolnum></citerefentry>. + This is easily done using the + <constant>SD_ID128_FORMAT_STR</constant> and <function>SD_ID128_FORMAT_VAL()</function> macros. For + more information see + <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para><function>sd_id128_to_string()</function> always succeeds + and returns a pointer to the string array passed in. + <function>sd_id128_from_string()</function> returns 0 on success, in + which case <parameter>ret</parameter> is filled in, or a negative + errno-style error code.</para> + </refsect1> + + <xi:include href="libsystemd-pkgconfig.xml" /> + + <refsect1> + <title>See Also</title> + + <para> + <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd-id128</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry project='man-pages'><refentrytitle>printf</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |