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1/*! \page queryformat Query formats2 3As it is impossible to please everyone with one style of query output, RPM4allows you to specify what information should be printed during a query5operation and how it should be formatted.6 7\section queryformat_tags Tags8 9All of the information a package contains, apart from signatures and the10actual files, is in a part of the package called the header. Each piece11of information in the header has a tag associated with it which allows12RPM to to tell the difference between the name and description of a13package.14 15To get a list of all of the tags your version of RPM knows about, run the16command 'rpm --querytags'. It will print out a list like (but much longer17then) this:18 19\verbatim20    BUILDHOST21    BUILDTIME22    DESCRIPTION23    EPOCH24    INSTALLTIME25    NAME26    RELEASE27    SIZE28    SUMMARY29    VERSION30\endverbatim31 32Each of these tags also has a version with a RPMTAG_ prefix, such as33RPMTAG_NAME. You can use this tags with or without the RPMTAG_ prefix.34 35A tag can consist of one element or an array of elements. Each element can36be a string or number only.37 38\section queryformat_format Query Formats39 40A query format is passed to RPM after the --queryformat argument, and normally41should be enclosed in quotes. This query format is then used to print42the information section of a query.43 44The query format is similar to a C style printf string, which the printf(2)45man page provides a good introduction to. However, as RPM already knows the46type of data that is being printed, you must omit the type specifier. In47its place put the tag name you wish to print enclosed in curly braces48({}). For example, the following RPM command prints the names and sizes49of all of the packages installed on a system:50 51\verbatim52    rpm -qa --queryformat "%{NAME} %{SIZE}\n"53\endverbatim54 55If you want to use printf formatters, they go between the % and {. To56change the above command to print the NAME in the first 30 bytes and57right align the size to, use:58 59\verbatim60    rpm -qa --queryformat "%-30{NAME} %10{SIZE}\n"61\endverbatim62 63\section queryformat_arrays Arrays64 65RPM uses many parallel arrays internally. For example, file sizes and 66file names are kept as an array of numbers and an array of strings67respectively, with the first element in the size array corresponding68to the first element in the name array. 69 70To iterate over a set of parallel arrays, enclose the format to be used71to print each item in the array within square brackets ([]). For example,72to print all of the files and their sizes in the slang-devel package73followed by their sizes, with one file per line, use this command:74 75\verbatim76    rpm -q --queryformat "[%-50{FILENAMES} %10{FILESIZES}\n]" slang-devel77\endverbatim78 79Note that since the trailing newline is inside of the square brackets, one80newline is printed for each filename.81 82A popular query format to try to construct is one that prints the83name of a package and the name of a file it contains on one line, 84repeated for every file in the package. This query can be very useful85for passing information to any program that's line oriented (such as86grep or awk). If you try the obvious,87 88\verbatim89    rpm -q --queryformat "[%{NAME} %{FILENAMES}\n]" cdp90\endverbatim91 92you'll see RPM complain about an "array iterator used with different93sized arrays". Internally, all items in RPM are actually arrays, so the94NAME is a string array containing one element. When you tell RPM to iterate95over the NAME and FILENAMES elements, RPM notices the two tags have96different numbers of elements and complains.97 98To make this work properly, you need to tell RPM to always print the first99item in the NAME element. You do this by placing a '=' before the tag100name, like this:101 102\verbatim103    rpm -q --queryformat "[%{=NAME} %{FILENAMES}\n]" cdp104\endverbatim105 106which will give you the expected output.107 108\verbatim109    cdp /usr/bin/cdp110    cdp /usr/bin/cdplay111    cdp /usr/man/man1/cdp.1112\endverbatim113 114\section queryformat_formatting Formatting Tags115 116One of the weaknesses with query formats is that it doesn't recognize117that the INSTALLTIME tag (for example) should be printed as a date instead118of as a number. To compensate, you can specify one of a few different119formats to use when printing tags by placing a colon followed the formatting 120name after the tag name. Here are some examples:121 122\verbatim123    rpm -q --queryformat "%{NAME} %{INSTALLTIME:date}\n" fileutils124    rpm -q --queryformat "[%{FILEMODES:perms} %{FILENAMES}\n]" rpm125    rpm -q --queryformat \126	"[%{REQUIRENAME} %{REQUIREFLAGS:depflags} %{REQUIREVERSION}\n]" \127	vlock128\endverbatim129 130The :shescape may be used on plain strings to get a string which can pass131through a single level of shell and give the original string.132 133Formatting names "humansi" and "humaniec" display a number in a human134readable format in SI resp IEC 80000 standard.135humansi uses 1K = 1000, 1M = 1000000, ...136humaniec uses 1K = 1024, 1M = 1048576, ...137 138The formatting tags are documented in rpm (8) manual in the QUERY OPTIONS139section.140 141\section queryformat_expressions Query Expressions142 143Simple conditionals may be evaluated through query expressions. Expressions144are delimited by %|...|. The only type of expression currently supported145is a C-like ternary conditional, which provides simple if/then/else146conditions. For example, the following query format display "present" if147the SOMETAG tag is present, and "missing" otherwise:148 149\verbatim150    %|SOMETAG?{present}:{missing}|151\endverbatim152 153Notice that the subformats "present" and "missing" must be inside of curly154braces.155 156\verbatim157    rpm -qa --queryformat "%-30{NAME} %|PREINPROG?{%{PREINPROG}}:{no}|\n"158\endverbatim159 160*/161