Provided by: pcp_6.3.3-1_amd64 
NAME
pmcpp - simple preprocessor for the Performance Co-Pilot
SYNOPSIS
pmcpp [-Prs?] [-D name[=value] ...] [-I dir ...] [[infile] [outfile]]
DESCRIPTION
pmcpp provides a very simple pre-processor originally designed for manipulating Performance Metric Name
Space (PMNS) files for the Performance Co-Pilot (PCP), but later generalized to provide conditional
blocks, include file processing, in-line shell command execution and macro substitution for arbitrary
files. It is most commonly used internally to process the PMNS file(s) after pmLoadNameSpace(3) or
pmLoadASCIINameSpace(3) is called and to pre-process the configuration files for pmlogger(1).
Input lines are read from infile (or standard input if infile is not specified), processed and written to
outfile (standard output if outfile is not specified).
All C-style comments of the form /* ... */ are stripped from the input stream.
There are no predefined macros for pmcpp although macros may be defined on the command line using the -D
option, where name and value must follow the same rules as described below for the #define directive.
pmcpp accepts the following directives in the input stream (like cpp(1)):
• #include "filename"
or
#include <filename>
In either case the directory search path for filename tries filename first, then the directory for the
command line infile (if any), followed by any directories named in -I command line arguments, and
finally the $PCP_VAR_DIR/pmns directory (the latter is for backwards compatibility with earlier
versions of pmcpp and the implied used from pmLoadASCIINameSpace(3)). #include directives may be
nested, up to a maximum depth of 5.
• #shell "command"
or
#shell 'command'
The shell command will be executed and the standard output is inserted into the stream of data to be
processed by pmcpp. Functionally this is similar to a #include directive, except input lines are read
from a command rather than a file. The #shell directive is most useful for including or excluding
#define or #undef directives based on run-time logic in the command.
• #define name value
or
#define name "value"
or
#define name 'value'
Defines a value for the macro name which must be a valid C-style name, so leading alphabetic or
underscore followed by zero or more alphanumerics or underscores. value is optional (and defaults to
an empty string). There is no character escape mechanism, but either single quotes or double quotes
may be used to define a value with special characters or embedded horizontal white space (no
newlines).
• #undef name
Removes the macro definition, if any, for name.
• #ifdef name
...
#endif
or
#ifndef name
...
#endif
The enclosing lines will be stripped or included, depending if the macro name is defined or not.
• #else
Within a #ifdef or #ifndef block, #else may be used to delimit lines to be included if the preceding
``if'' condition is false.
Macro substitution is achieved by breaking the input stream into words separated by white space or
characters that are not valid in a macro name, i.e. not alphanumeric and not underscore. Each word is
checked and if it matches a macro name, the word is replaced by the macro value, otherwise the word is
unchanged.
There is generally one output line for each input line, although the line may be empty if the text has
been stripped due to the handling of comments or conditional directives. When there is a change in the
input stream, an additional output line is generated of the form:
# lineno "filename"
to indicate the following line of output corresponds to line number lineno of the input file filename.
OPTIONS
The available command line options are:
-D name[=value], --define=name[=value]
Defines a macro with an optional value, as described earlier.
-I dir, --include=dir
An additional directory to search for include files.
-P Suppresses the generation of the linemarker lines, described above.
-s, --shell
Changes the expected input style from C-like to shell-like (where # is a comment prefix). This
forces the following changes in pmcpp behaviour:
• The control prefix character changes from # to %, so for example %include instead of #include,
and %ifdef instead of #ifdef.
• No C-style comment stripping is performed.
-r, --restrict
Provide finer control of macro expansion - this option restricts macro substitution to words that
match the patterns #name or #{name} or if -s is specified, then %name or %{name}. In this mode, the
macro name alone in the input stream will never be expanded, however in control lines (like #ifdef)
the macro name should appear alone with out the prefix character or the curly braces (refer to the
EXAMPLES below).
-?, --help
Display usage message and exit.
Important cpp(1) features that are not supported by pmcpp include:
• Macros with parameters - the pmcpp macros support only parameterless string substitution.
• #if expr
...
#endif
• Nested use of #ifdef or #ifndef.
• Stripping C++ style comments, as in // comment.
• Error recovery - the first error encountered by pmcpp will be fatal.
• cpp(1) command line options like -o, -W, -U, and -x.
EXAMPLES
┌──────────────────────────────────────────────┐
│ Command: pmcpp │
├────────────────────────┬─────────────────────┤
│ Input │ Output │
├────────────────────────┼─────────────────────┤
│ │ # 1 "<stdin>" │
│ #define MYDOMAIN 27 │ │
│ │ │
│ root { │ root { │
│ foo MYDOMAIN:0:0 │ foo 27:0:0 │
│ } │ } │
└────────────────────────┴─────────────────────┘
For the following examples, the file frequencies contains the lines:
%define dk_freq 1minute
%define cpu_freq '15 sec'
┌────────────────────────────────────────────────────────────────────┐
│ Command: pmcpp -rs │
├───────────────────────────────────┬────────────────────────────────┤
│ Input │ Output │
├───────────────────────────────────┼────────────────────────────────┤
│ # get logging frequencies │ # get logging frequencies │
│ # e.g. dk_freq macro │ # e.g. dk_freq macro │
│ %include "frequencies" │ │
│ │ │
│ log mandatory on %dk_freq { │ log mandatory on 1minute { │
│ disk.dev │ disk.dev │
│ } │ } │
│ │ │
│ # note no %want_cpu here │ # note no %want_cpu here │
│ %ifdef want_cpu │ │
│ %define cpu_pfx 'kernel.all.cpu.' │ │
│ log mandatory on %cpu_freq { │ │
│ %{cpu_pfx}user │ │
│ %{cpu_pfx}sys │ │
│ } │ │
│ %endif │ │
└───────────────────────────────────┴────────────────────────────────┘
┌───────────────────────────────────────────────────────────────────┐
│ Command: pmcpp -rs -D want_cpu │
├───────────────────────────────────┬───────────────────────────────┤
│ Input │ Output │
├───────────────────────────────────┼───────────────────────────────┤
│ # get logging frequencies │ # get logging frequencies │
│ # e.g. dk_freq macro │ # e.g. dk_freq macro │
│ %include "frequencies" │ │
│ │ │
│ log mandatory on %dk_freq { │ log mandatory on 1min { │
│ disk.dev │ disk.dev │
│ } │ } │
│ │ │
│ # note no %want_cpu here │ # note no %want_cpu here │
│ %ifdef want_cpu │ │
│ %define cpu_pfx 'kernel.all.cpu.' │ │
│ log mandatory on %cpu_freq { │ log mandatory on 15 sec { │
│ %{cpu_pfx}user │ kernel.all.cpu.user │
│ %{cpu_pfx}sys │ kernel.all.cpu.sys │
│ } │ } │
│ %endif │ │
└───────────────────────────────────┴───────────────────────────────┘
PCP ENVIRONMENT
Environment variables with the prefix PCP_ are used to parameterize the file and directory names used by
PCP. On each installation, the file /etc/pcp.conf contains the local values for these variables. The
$PCP_CONF variable may be used to specify an alternative configuration file, as described in pcp.conf(5).
For environment variables affecting PCP tools, see pmGetOptions(3).
SEE ALSO
cpp(1), pmLoadASCIINameSpace(3), pmLoadNameSpace(3), pcp.conf(5), pcp.env(5) and PMNS(5).
Performance Co-Pilot PMCPP(1)