X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsd_bus_message_append.xml;h=26af67cd3890e17ef4513816fd56a309b8a42a11;hp=b14a6c985cdcb57b5a1f5a2d49e738ae921581f1;hb=3ff66cca1cae924f9b6bd4dae3587dd854c77a16;hpb=b8bde11658366290521e3d03316378b482600323 diff --git a/man/sd_bus_message_append.xml b/man/sd_bus_message_append.xml index b14a6c985..26af67cd3 100644 --- a/man/sd_bus_message_append.xml +++ b/man/sd_bus_message_append.xml @@ -1,27 +1,27 @@ - + - @@ -45,8 +45,10 @@ along with systemd; If not, see . sd_bus_message_append + sd_bus_message_appendv - Attach parts of message based on a format string + Attach fields to a D-Bus message based on a type + string @@ -57,25 +59,36 @@ along with systemd; If not, see . int sd_bus_message_append sd_bus_message *m const char *types - ... + … + + + int sd_bus_message_appendv + sd_bus_message *m + const char *types + va_list ap + + Description - The sd_bus_message_append function appends - a sequence of items to message m. The - format string types describes the types of - arguments that follow. + The sd_bus_message_append() function + appends a sequence of fields to the D-Bus message object + m. The type string + types describes the types of the field + arguments that follow. For each type specified in the type string, + one or more arguments need to be specified, in the same order as + declared in the type string. - The format string is composed of the elements shown in the + The type string is composed of the elements shown in the table below. It contains zero or more single "complete types". Each complete type may be one of the basic types or a fully - described container type. A container type may be a structure, a - variant type code, an array with its element type, or a dictionary - with its entry type. The format string is + described container type. A container type may be a structure with + the contained types, a variant, an array with its element type, or + a dictionary entry with the contained types. The type string is NUL-terminated. In case of a basic type, one argument of the corresponding @@ -87,28 +100,41 @@ along with systemd; If not, see . Arguments corresponding to this nested sequence follow the same rules as if they were not nested. - A variant is denoted by v. Correspoding - arguments must include a format string denoting a complete type, + A variant is denoted by v. Corresponding + arguments must begin with a type string denoting a complete type, and following that, arguments corresponding to the specified type. An array is denoted by a followed by a - complete type. Corresponding arguments must include the size of - the array, and then repeated this number of times, arguments - corresponding to the nested type. + complete type. Corresponding arguments must begin with the number of + entries in the array, followed by the entries themselves, + matching the element type of the array. A dictionary is an array of dictionary entries, denoted by a followed by a pair of complete types between { and }. The first of those - types must be a basic type. Corresponding arguments must include - the size of the dictionary, and then repeated this number of - times, arguments corresponding to each of the two nested - types. + types must be a basic type. Corresponding arguments must begin + with the number of dictionary entries, followed by a pair of + values for each entry matching the element type of + the dictionary entries. + + The sd_bus_message_appendv() is equivalent to + the function sd_bus_message_append(), + except that it is called with a va_list instead of + a variable number of arguments. This function does not call the + va_end() macro. Because it invokes the + va_arg() macro, the value of ap + is undefined after the call. + + For further details on the D-Bus type system, please consult + the D-Bus + Specification. - Item format specifiers + Item type specifiers - + @@ -120,6 +146,7 @@ along with systemd; If not, see . SD_BUS_TYPE_ARRAY array determined by array type and size + int, followed by array contents @@ -127,6 +154,7 @@ along with systemd; If not, see . SD_BUS_TYPE_VARIANT variant determined by the type argument + signature string, followed by variant contents @@ -134,6 +162,7 @@ along with systemd; If not, see . SD_BUS_TYPE_STRUCT_BEGIN array start determined by the nested types + structure contents ) @@ -146,6 +175,7 @@ along with systemd; If not, see . SD_BUS_TYPE_DICT_ENTRY_BEGIN dictionary entry start determined by the nested types + dictionary contents } @@ -155,10 +185,16 @@ along with systemd; If not, see .
+ + For types "s" and "g" (unicode string or signature), the pointer may be + NULL, which is equivalent to an empty string. See + sd_bus_message_append_basic3 + for the precise interpretation of those and other types. + - Types string grammar + Types String Grammar types ::= complete_type* complete_type ::= basic_type | variant | structure | array | dictionary @@ -179,7 +215,7 @@ dictionary ::= "a" "{" basic_type complete_type "}" sd_bus_message *m; -... +… sd_bus_message_append(m, "s", "a string"); Append all types of integers: @@ -194,7 +230,7 @@ uint32_t t = 7; double d = 8.0; sd_bus_message_append(m, "ynqiuxtd", y, n, q, i, u, x, t, d); - Append a structure composed of string and a D-Bus path: + Append a structure composed of a string and a D-Bus path: sd_bus_message_append(m, "(so)", "a string", "/a/path"); @@ -219,8 +255,8 @@ sd_bus_message_append(m, "ynqiuxtd", y, n, q, i, u, x, t, d); Return Value - On success, this call returns 0 or a positive - integer. On failure, this call returns a negative + On success, these functions return 0 or a positive + integer. On failure, these functions return a negative errno-style error code. @@ -232,7 +268,7 @@ sd_bus_message_append(m, "ynqiuxtd", y, n, q, i, u, x, t, d); sd_bus_open_user() and other functions described here are available as a shared library, which can be compiled and linked to with the - libsystemd-bus pkg-config1 + libelogind-bus pkg-config1 file. @@ -242,12 +278,8 @@ sd_bus_message_append(m, "ynqiuxtd", y, n, q, i, u, x, t, d); systemd1, sd-bus3, - sd_bus_new3, - sd_bus_ref3, - sd_bus_unref3, - ssh1, - systemd-machined.service8, - machinectl1 + sd_bus_message_append_basic3, + sd_bus_message_append_array3