pmcpp(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXAMPLES | PCP ENVIRONMENT | SEE ALSO | COLOPHON

PMCPP(1)                 General Commands Manual                PMCPP(1)

NAME         top

       pmcpp - simple preprocessor for the Performance Co-Pilot

SYNOPSIS         top

       pmcpp [-Prs?]  [-D name[=value] ...]  [-I dir ...]  [[infile]
       [outfile]]

DESCRIPTION         top

       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         top

       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 %include
          for example.
       •  No 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).

       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.

       -?, --help
          Display usage message and exit.

EXAMPLES         top

       ┌──────────────────────────────────────────────┐
       │ 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         top

       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         top

       cpp(1), pmLoadASCIINameSpace(3), pmLoadNameSpace(3), pcp.conf(5),
       pcp.env(5) and PMNS(5).

COLOPHON         top

       This page is part of the PCP (Performance Co-Pilot) project.
       Information about the project can be found at 
       ⟨http://www.pcp.io/⟩.  If you have a bug report for this manual
       page, send it to [email protected].  This page was obtained from the
       project's upstream Git repository
       ⟨https://github.com/performancecopilot/pcp.git⟩ on 2024-06-14.
       (At that time, the date of the most recent commit that was found
       in the repository was 2024-06-14.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       [email protected]

Performance Co-Pilot                                            PMCPP(1)

Pages that refer to this page: pmlogger(1)pmloadasciinamespace(3)pmns(5)