Visit Our UNIX and Linux User Community

Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

xmlif(1) [redhat man page]

XMLIF(1)																  XMLIF(1)

xmlif - conditional processing instructions for XML SYNOPSIS
xmlif [attrib=value...] DESCRIPTION
xmlif filters XML according to conditionalizing markup. This can be useful for formatting one of several versions of an XML document depending on conditions passed to the command. Attribute/value pairs from the command line are matched against the attributes associated with certain processing instructions in the docu- ment. The instructions are <?if> and its inverse <?if not>, <?elif> and its inverse <?elif not>, <?else>, and <?fi>. Argument/value pairs given on the command line are checked against the value of corresponding attributes in the conditional processing instructions. An `attribute match' happens if an attribute occurs in both the command-line arguments and the tag, and the values match. An `attribute mismatch' happens if an attribute occurs in both the command-line arguments and the tag, but the values do not match. Spans between <?if> or <?elif> and the next conditional processing instruction at the same nesting level are passed through unaltered if there is at least one attribute match and no attribute mismatch; spans between <?if not> and <?elif not> and the next conditional process- ing instruction are passed otherwise. Spans between <?else> and the next conditional-processing tag are passed through only if no previous span at the same level has been passed through. <?if> and <?fi> (and their `not' variants) change the current nesting level; <?else> and <?elif> do not. All these processing instructions will be removed from the output produced. Aside from the conditionalization, all other input is passed through untouched; in particular, entity references are not resolved. Value matching is by string equality, except that "|" in an attribute value is interpreted as an alternation character. Thus, saying foo='red|blue' on the command line enables conditions red and blue. Saying color='black|white' in a tag matches command-line conditions color='black' and color='white'. Here is an example: Always issue this text. <?if condition='html'> Issue this text if 'condition=html' is given on the command line. <?elif condition='pdf|ps'> Issue this text if 'condition=pdf' or 'condition=ps' is given on the command line. <?else> Otherwise issue this text. <?fi> Always issue this text. FUTURE DIRECTIONS
The mark-up used by this tool is not set in stone, and may change in the near future. AUTHOR
Eric S. Raymond. Sep 26 2002 XMLIF(1)

Check Out this Related Man Page

UNIFDEF(1)						    BSD General Commands Manual 						UNIFDEF(1)

unifdef, unifdefall -- remove preprocessor conditionals from code SYNOPSIS
unifdef [-ceklst] [-Ipath] [-Dsym[=val]] [-Usym] [-iDsym[=val]] [-iUsym] ... [-o output] [file] unifdefall [-Ipath] ... file DESCRIPTION
The unifdef utility selectively processes conditional cpp(1) directives. It removes from a file both the directives and any additional text that they specify should be removed, while otherwise leaving the file alone. The unifdef utility acts on #if, #ifdef, #ifndef, #elif, #else, and #endif lines, and it understands only the commonly-used subset of the expression syntax for #if and #elif lines. It handles integer values of symbols defined on the command line, the defined() operator applied to symbols defined or undefined on the command line, the operators !, <, >, <=, >=, ==, !=, &&, ||, and parenthesized expressions. Anything that it does not understand is passed through unharmed. It only processes #ifdef and #ifndef directives if the symbol is specified on the command line, otherwise they are also passed through unchanged. By default, it ignores #if and #elif lines with constant expressions, or they may be processed by specifying the -k flag on the command line. The unifdef utility also understands just enough about C to know when one of the directives is inactive because it is inside a comment, or affected by a backslash-continued line. It spots unusually-formatted preprocessor directives and knows when the layout is too odd to handle. A script called unifdefall can be used to remove all conditional cpp(1) directives from a file. It uses unifdef -s and cpp -dM to get lists of all the controlling symbols and their definitions (or lack thereof), then invokes unifdef with appropriate arguments to process the file. Available options: -Dsym[=val] Specify that a symbol is defined, and optionally specify what value to give it for the purpose of handling #if and #elif directives. -Usym Specify that a symbol is undefined. If the same symbol appears in more than one argument, the last occurrence dominates. -c If the -c flag is specified, then the operation of unifdef is complemented, i.e., the lines that would have been removed or blanked are retained and vice versa. -e Because unifdef processes its input one line at a time, it cannot remove preprocessor directives that span more than one line. The most common example of this is a directive with a multi-line comment hanging off its right hand end. By default, if unifdef has to process such a directive, it will complain that the line is too obfuscated. The -e option changes the behaviour so that, where pos- sible, such lines are left unprocessed instead of reporting an error. -k Process #if and #elif lines with constant expressions. By default, sections controlled by such lines are passed through unchanged because they typically start ``#if 0'' and are used as a kind of comment to sketch out future or past development. It would be rude to strip them out, just as it would be for normal comments. -l Replace removed lines with blank lines instead of deleting them. -o output The argument given is the name of an output file to be used instead of the standard output. This file can be the same as the input file. -s Instead of processing the input file as usual, this option causes unifdef to produce a list of symbols that appear in expressions that unifdef understands. It is useful in conjunction with the -dM option of cpp(1) for creating unifdef command lines. -t Disables parsing for C comments and line continuations, which is useful for plain text. -iDsym[=val] -iUsym Ignore #ifdefs. If your C code uses #ifdefs to delimit non-C lines, such as comments or code which is under construction, then you must tell unifdef which symbols are used for that purpose so that it will not try to parse comments and line continuations inside those #ifdefs. One specifies ignored symbols with -iDsym[=val] and -iUsym similar to -Dsym[=val] and -Usym above. -Ipath Specifies to unifdefall an additional place to look for #include files. This option is ignored by unifdef for compatibility with cpp(1) and to simplify the implementation of unifdefall. The unifdef utility copies its output to stdout and will take its input from stdin if no file argument is given. The unifdef utility works nicely with the -Dsym option of diff(1). DIAGNOSTICS
Too many levels of nesting. Inappropriate #elif, #else or #endif. Obfuscated preprocessor control line. Premature EOF (with the line number of the most recent unterminated #if). EOF in comment. The unifdef utility exits 0 if the output is an exact copy of the input, 1 if not, and 2 if in trouble. SEE ALSO
cpp(1), diff(1) HISTORY
The unifdef command appeared in 4.3BSD. ANSI C support was added in FreeBSD 4.7. BUGS
Expression evaluation is very limited. Preprocessor control lines split across more than one physical line (because of comments or backslash-newline) cannot be handled in every situation. Trigraphs are not recognized. There is no support for symbols with different definitions at different points in the source file. The text-mode and ignore functionality does not correspond to modern cpp(1) behaviour. BSD
June 5, 2009 BSD

Featured Tech Videos