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CFPEEK |
CFPEEK |
Sergey Poznyakoff |
Cfpeek User Manual (split by chapter): 
The format of cfpeek invocation is:
cfpeek options file [keys]
where options are command line options, file is the configuration file to operate upon, and optional keys are pathnames of the keywords to locate in that configuration file.
If keys are supplied, cfpeek, for each key,
looks up in the parse tree for any nodes matching the key and prints
them on the standard output. An error message is displayed for any
key which has no matching statements in the input file. In this case,
program continues iterating over the rest of keys. When the
list is exhausted, cfpeek will exit with the status 1
(see Exit Codes).
If either -f (--file) or -e
(--expression) has been given, a Scheme expression or the default
cfpeek function is evaluated for each matching node. If
-e (--expression) is given, the node is passed to it in
the global ‘node’ variable. Otherwise, if -f
(--file) is given, the node is passed as argument to
cfpeek function.
If both --file=script and --expression=expression options are given, the script file script is loaded first, and the expression is evaluated for each matching node. The expression can then refer to any variables and call any functions defined in the script.
If no keys are supplied, the program operates as if given a single ‘.*’ key (see Patterns), which matches any node in the parse tree (i.e., it iterates over the entire parse tree).
By default cfpeek treats keys as wildcard patterns.
When matching statement identifiers (keywords), two characters have special
meaning: ‘%’ and ‘*’.
A ‘%’ character in place of an identifier matches any single keyword. Thus, e.g.:
cfpeek file.conf .%.bar.baz
will match ‘.foo.bar.baz’, ‘.qux.bar.baz’, but will not match ‘.bar.baz’ or ‘.x.y.bar.baz’.
A single ‘*’ character in place of a keyword matches zero or more keywords appearing in its place, so that:
cfpeek file.conf .*.bar.baz
The tags in block statement are matched using the traditional globbing patterns. See http://www.manpagez.com/man/3/fnmatch.
For example, this:
cfpeek file.conf .*.program="mh-*"
will match any ‘program’ block statement whose tag begins with ‘mh-’.
Set output format flags. The argument is a comma-separated list of format flags and relative movement options. Relative movement options select another node, relative to the one found. They are:
Find a parent of the matching node, which has id as its identifier.
Find a child of the matching node, which has id as its identifier.
Find a sibling of the matching node, which has id as its identifier.
Ascend n parent nodes and print the node at which the ascent stopped.
Descend n child nodes.
Any number of relative movement options can be specified. They are executed in the order of their appearance in the --format statement. For example, --format=up=2,sibling=foo,child=bar means: ascend two levels of hierarchy, find a node named ‘foo’, look for a node named ‘bar’ among the children of that node and print the result.
If evaluation of the relative movement options results in an empty node (e.g. the ‘up’ option attempts to go past the root of the tree), nothing is output.
The delim flag controls how keyword paths is printed:
Sets path component delimiter, instead of the default ‘.’.
The following flags control the amount of information printed for each node. These are boolean flags: when prefixed with ‘no’ they have the meaning opposite to the described.
Print source location of each configuration statement. A location is printed as the file name, followed by a semicolon, followed by the line number and another semicolon. Locations are separated from the rest of output by a single space character.
Print statement paths.
Print statement values.
Always quote string values.
Never quote string values.
Print non-printable characters as C hex escapes. This option is ignored if ‘noquote’ is set.
Descend into subnodes. Set default options.
The default format options are: ‘path,value,quote,descend’.
Suppress error diagnostics. See quiet.
The following options modify the way cfpeek processes the
parse tree and search keys.
Use literal matching, instead of pattern matching. See literal.
Before further processing, sort parse tree lexicographically in ascending order.
Output at most number matches for each key.
Set parser type for the input file. The argument is one of: ‘grecs’, ‘path’, ‘meta1’, ‘bind’, ‘dhcpd’, and ‘git’ (case-insensitive). See Formats, for a description of each type.
Reduce the parse tree, so that each keyword occurs no more than once at each tree level.
Set a keyword path to value. The produced parse tree node will be processed as usual.
The following options control the scripting facility of
cfpeek.
Apply this expression to each node found. The global variable
node is set to the node being processed before evaluating.
When used together with --file=script, the expression
can refer to any variables and call any functions defined in the
script file.
Load the script file. Unless --expression is also given, the script must define the function named ‘cfpeek’ which takes a node as its only argument. This function will be called for each matching node.
If --expression is given, this behavior is suppressed. It is then the responsibility of the expression to call any functions defined in this file.
The --init=expr (-i expr) option provides an initialization expression expr. This expression is evaluated once, after loading the script file, if one is specified, and before starting the main loop.
Select scripting language to use. This option is reserved for further use. As of version 1.2, the only possible value for script-language is ‘scheme’.
The options described below control the preprocessor facility. They are meaningful only for ‘GRECS’ and ‘BIND’ configuration files. Preprocessor is not used for another configuration file formats.
Define the preprocessor symbol name as having value, or empty. See Preprocessor.
Add dir to include search path.
See #include.
Disable preprocessor. see Preprocessor.
Use command instead of the default preprocessor. see Preprocessor.
The options below enable trace output which helps understand how
configuration parser works. They are mainly useful for
cfpeek developers.
Trace configuration file lexer.
Trace configuration file parser.
Print a concise usage summary and exit.
Print a summary of command line syntax and exit.
Print the program version and exit.
Cfpeek User Manual (split by chapter):
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