Provided by: icmake_12.03.00-1ubuntu1_amd64 
NAME
icmconf - Configuration file for the icmbuild(1) program maintenance script
DESCRIPTION
The icmconf configuration file is used to specify and fine-tune the program maintenance performed by the
icmbuild(1) program and script. It can be used to activate and specify various directives that determine
how the program or library maintenance is performed.
Since icm() version 11.00.00 icm() offers Single Pre-Compiled Headers (SPCH) and multi-threaded
source-file compilation, commonly reducing the construction times of projects to around 30-40% of the
original construction times: refer to the #define SPCH and #define MULTICOMP directives below for
details.
Icmconf’s directives are biased towards the construction of C++ programs, but program maintenance for
other languages (e.g., C) can also easily be configured.
The icmbuild(1) script ignores empty lines and lines whose first non-blank characters are two consecutive
forward slashes (//). Long lines can be split over multiple lines by writing a final backslash character
at lines continuing at the next line (refer to the icmake(1) man-page for further details).
CLASS DEPENDENCIES
Traditional make-utilities recompile all dependent sources once header files are modified. When
developing C++ programs this is hardly ever requird, as adding new member functions to classes does not
require you to recompile already existing source files. Recompilation is required when the data member
organization of classes is altered.
To handle class dependencies in a more sensible way, icmake(1) checks class dependencies using its
support programs icm-dep, visiting the classes listed in the CLASSES file if icmconf’s USE_ALL directive
was specified. If a directory mentioned in the CLASSES file contains a file having a name that’s equal to
the name specified at the USE_ALL parameter, then all sources of classes that depend on that particular
class are also recompiled. In practice this means that when you change the data organization of a class
you only need to touch it that directory the file whose name was specified by the USE_ALL directive.
E.g., if your class is named Data, its sources are in the sub-directory ./data, and #define USE_ALL "a"
was specified then after modifying the data organization of the class Data you only need to issue the
command touch data/a. Subsequently, at the next icmbuild call all sources in ./data as well as all
sources in directories whose (header) files include data.h are recompiled as well.
Likewise, if #define SPCH or (deprecated) #define PRECOMP was used, then a similar action is performed
for the precompiled headers: if a local file that’s (directly or indirectly) included by internal header
files has changed, then (having specified SPCH) the Single Pre-Compiled Header (SPCH) file is recompiled
or (deprecated: having specified PRECOMP the modified class headers are recompiled).
The icmbuild(1) script itself does not inspect these dependencies, but calls the support programs
icm-spch and icm-dep to perform the requird tests. The short usage descriptions of these programs are
written to the standard output stream when calling, respectively icmake -S and icmake -d.
DEFINES IN ICMCONF
All of the following #defines are required except those that are shown as commented #defines (e.g.,
//#define REFRESH).
o //#define ADD_LIBRARIES ""
when a program must be linked against additional libraries (other than the name of the program’s
library itself (specified at LIBRARY) then those libraries should be specified here. E.g., when a
program is linked against libbobcat then the specification is:
#define ADD_LIBRARIES "bobcat"
If your program is linked against multiple libraries, then use a blank-separated list of libraries
(like #define ADD_LIBRARIES "math bobcat");
o //#define ADD_LIBRARY_PATHS ""
this directtive must be specified if ADD_LIBRARIES is also specified, although it may be specified
as an empty string. When additional libraries (specified at ADD_LIBRARIES) are located in
non-standard library locations (e.g., not in /lib and /usr/lib) then these additional paths are
(blank space separated) specified here. Specify only the paths, not the -L flags.
It is stronly advised to specify full pathnames here. Relative path specifications can be used by
specify paths relative to the directory that is specified at the TMP_DIR directive (see below);
o //#define CLS
the clear screen directive. If defined tput clear is called to clear the terminal screen before
starting compilations. By default it is not defined. Alternatively the -c option can be passed to
icmbuild;
o #define CXX "g++"
the C++ compiler to use. For a C compiler specify, e.g., #define CC "gcc". Their settings are
overruled by identically named environment variables. If only C files are compiled then #define
CXX can be omitted.
By specifying, e.g., #define CXX "ccache g++" compilations use caching facilities, which may
impressively reduce recompilation times. Refer to the cccache(1) man-page for details.
o #define CXXFLAGS "-Werror -Wall -O2"
C++ compiler options to use (here showing the default options). When the C compiler is used, use
#define CFLAGS rather than CXXFLAGS. Their settings are overruled by identically named environment
variables. If only C files are compiled then #define CXXFLAGS can be omitted.
Additional options can be defined by adding them to the CXXFLAGS definition. In addition,
compilations use the environment variable ICMAKE_CPPSTD to set the C++ standard to use. E.g.,
after defining
ICMAKE_CPPSTD=--std=c++26
the compiler uses the options
--std=c++26 -Werror -Wall -O2
o //#define DEFCOM "..."
a DEFCOM directive may be added to the icmconf file (the icmstart(1) script can do this for you).
It can be specified as:
#define DEFCOM "program"
in which case icmbuild does program maintenance, or as
#define DEFCOM "library"
in which case icmbuild does library maintenance.;
o //#define ICM_DEP "-V go"
the existence and implied existence of USE_ALL files (see the description of the USE_ALL
directive). When the (deprecated) PRECOMP directive is specified the recency of precompiled
headers is ensured (see also the SPCH description, below). By default icm_dep is called with the
shown default arguments. If icm_dep should not be called define ICM_DEP as an empty string ("").
Icmake(1)’s man-page contains a separate section about the icm_dep support program;
o #define IH ".ih"
the extension used for internal header files. See #define PRECOMP below. If PRECOMP is specified
ttIH) must also be specified;
o //#define LDFLAGS ""
linker options to use. By default no options are passed to the linker. Its setting is overruled by
an identically named environment variable;
o //#define LIBRARY "modules"
by defining this directive a local library is constructed. When a binary program is built it is
linked against this library rather than to the individual object modules.
If a library instead of a program must be constructed (see also the DEFCOM directive), then the
LIBRARY directive specifies the library’s base name (without the lib prefix and without the .a
extension). In that case source files are expected in sub-directories of the project’s main
directory (i.e., the directory containing icmconf). In that case avoid having source and header
files in the project’s main directory. Instead, move such files to a separate sub-directory;
o //#define MAIN "main.cc"
the source file in which the int main function is defined. This directive is required when doing
program (rather than library) maintenance.
Note: if source files are located in the project’s main directory but library maintenance is
intended (e.g., by specifying #define DEFCOM library) then define MAIN to specify a pseudo main
source, whose base name is the base name of the header file in the project’s main directory. This,
however, is considered a kludge, and should be avoided by moving those source and header files to
a separate sub-directory;
o //#define MULTICOMP "..."
Example: #define MULTICOMP "jobs -q"
This directive activates threaded compilation of source files. When used its first word specifies
the name of a file to contain information about which files must be compiled. This must be a plain
filename, not containing directory specifiers (like /).
The filename may be followed by option specifications:
o --nr (or -n)
when this option is specified the thread numbers compiling source files are written to the
standard output stream.
o --quiet (or -q)
When this options is not specified then the path names of the compiled object and source
files are written to the standard output stream. When it is specified once only the source
files’ directories and filenames are written to the standard output stream, and when it is
specified more than once no information about the compiled files is written to the standard
output stream.
o --threads nThreads (or -t nThreads)
by default the computer’s number of cores determines the number of threads being used when
compiling the source files. Optionally a different number of threads can be requested using
this option.
E.g., --threads 5.
o //#define NO_PRECOMP_WARNING"
when PRECOMP (now deprecated) is defined (see below) a warning is issued when a class-directory
does not contain a IH file. Such warnings are suppressed by defining NO_PRECOMP_WARNING. This
option is only considered when PRECOMP has been defined;
o #define OBJ_EXT ".o"
this directive specifies the extension of object modules created by the compiler;
o //#define PRECOMP "-x c++-header"
(deprecated, consider declaring #define SPCH instead)
define this directive to construct class-specific precompiled headers (in which case the IH)
directive must also be specified. Dependencies between (precompiled) headers are automatically
considered.
Existing precompiled headers are removed by icmbuild cleangch (or icmbuild clean. When source
files of other languages are compiled the PRECOMP’s -x argument must be adapted to those
languages.
If PRECOMP is defined then IH must also be defined;
o //#define REFRESH
define REFRESH to relink the binary program when icmbuild program is called, even though no file
was (re)compiled. This is useful when the program links to external libraries which were updated
separately from the currrent project;
o //#define SHARED
this directive is only interpreted when LIBRARY is also specified. If defined a shared library
(extension .so*) is built in addition to a static library (extension .a);
The shared library receives VERSION as its version number while soft links using VERSION’s (see
below) major version number an no version number are also made available. E.g., if VERSION is
defined as 1.02.03 and #define LIBRARY "demo" then the shared library becomes libdemo.so.1.02.03,
with libdemo.so.1 soft-linking to it, and libdemo.so soft-linking to libdemo.so.1;
o //#define SHAREDREQ ""
when creating a shared library SHAREDREQ specifies the names of libraries and library paths that
are required by the constructed shared library itself. E.g., if a library is found in
/usr/lib/special, assuming that the name of the required library is libspecial.so, then use the
specification #define SHAREDREQ "-L/usr/lib/special -lspecial". The /lib and /usr/lib paths are
usually automatically visited by the linker and do not have the be specified. This directive is
required (possibly as an empty string) if SHARED is defined;
o #define SOURCES "*.cc"
the pattern to locate sources in directories;
o //#define SPCH "..."
Example: #define SPCH ""
If SPCH is defined then IH must also be defined.
This directive activates using Single Pre-Compiled Headers (refer to the icmake(1) man-page for
details). The argument string can be empty, or it can contain a combination of the following
specifications:
o --keep regex (or -k regex)
keep (and do not inspect) include-specification(s) in the internal header matching regular
expressions in regex. If regex starts with f: (e.g., f:regex) then regex is the name of a
file whose non-empty line contains a regex. Otherwise regex contains a (POSIX extended)
regular expression, using (...)|(...) when specifying multiple regexes.
Example: -k xerr/xerr.
o --no-topdir (or -n)
Ignore the project’s top directory. This option is used in projects merely constructing a
library, instead of constructing a program (in which case the top-level directory commonly
contains a main.ih internal header file).
o //#define SPCH_FILE "..."
Example: #define SPCH_FILE "specs"
This directive can be used in combination with the #define SPCH directive. By default the headers
used to construct the SPCH are written to the file spch. If that name should not be used then use
the SPCH_FILE directive to specify another filename. The specified name must be a plain filename,
not containing directory specifiers (like /).
o #define TMP_DIR "tmp"
the directory in which intermediate results are stored. To avoid cross-device communications it’s
probably best to define TMP_DIR as a sub-directory of the project’s main directory;
o //#define USE_ALL "a"
when defining this directive icmbuild looks for directories containing files having the names
defined by the USE_ALL specification. All source files in those directories as well as all source
files in directories that (recursively) depend on the set of directories under consideration are
recompiled, after which the USE_ALL files are removed;
o //#define USE_ECHO ON
when defined as ON (rather than OFF) (system) commands executed by icmbuild are echoed;
o //#define USE_VERSION
when defined (it is defined by default) a file VERSION is read by icmconf to determine the
program’s or library’s version, and the project’s release years. The file VERSION must be
available in the project’s main directory and should contain lines like these:
VERSION=11.01.00
YEARS=1992-2024
)
PARSER MAINTENANCE
The following directives are available in cases where a program uses a parser generator creating a
parser class from a grammar specification. By default they’re all commented out.
o //#define PARSER_DIR ""
the sub-directory containing the parser’s specification file. If the PARSER_DIR directory is
specified then all other directives in this section must also be specified;
o //#define PARSFILES ""
if the parser specification file named at PARSSPEC itself includes additional specification files,
then patterns matching these additional grammar specification files should be specified here. The
pattern is interpreted in the directory specified at PARSER_DIR and could contain a subdirectory
name (e.g. specs/*). When files matching the pattern are modified then a new parser is created;
o //#define PARSFLAGS "-V"
the flags that are used when calling the program specified at PARSGEN;
o //#define PARSGEN "bisonc++"
the name of the program generating the parser;
o //#define PARSOUT "parse.cc"
the name of the file generated by the parser generator (used by icmbuild when checking the
timestamps of parser specification s);
o //#define PARSSPEC "grammar"
the name of the parser specification file. This file is expected in the directory specified by the
PARSER_DIR directive.
SCANNER MAINTENANCE
The following directives are available in cases where a program uses a scanner generator creating a
lexical scanner class from a set of regular expressions. By default they’re all commented out.
o #define SCANNER_DIR ""
the subdirectory containing the scanner’s specification file. If the SCANNER_DIR directory is
specified then all other directives in this section must also be specified;
o #define SCANFILES ""
if the lexical scanner specification file named at SCANSPEC itself includes additional
specification files, then patterns matching these additional lexer specification files should be
specified here. The pattern is interpreted in the directory specified at SCANNER_DIR and could
contain a subdirectory name (e.g. specs/*). When files matching the pattern are modified then a
new lexical scanner is created. By default no additional specification files are used;
o #define SCANFLAGS ""
the flags that are used when calling the program specified at SCANGEN;
o #define SCANGEN "flexc++"
the name of the program generating the lexical scanner;
o #define SCANOUT "lex.cc"
the name of the file generated by the lexical scanner (which is used by icmbuild when checking the
timestamps of scanner specification s).
o #define SCANSPEC "lexer"
the name of the lexical scanner specification file. This file is expected in the directory
specified by the SCANNER_DIR directive.
FILES
The mentioned paths are sugestive only and may be installation dependent:
o /usr/share/icmake/CLASSES
: example of an icmconf CLASSES file;
o /usr/share/icmake/icmconf
: default (skeleton) icmbuild resource files, like main.cc, usage.cc, etc.;
o /etc/icmake
: directory containing the default system-wide icmstart(1) configuration file;
o $HOME/.icmake
: optional user-defined directory containing user-defined specifications overruling the
system-wide definitions. This directory is the proper location for a file AUTHOR defining the
AUTHOR directive with the user’s name. E.g., my .icmake/AUTHOR file contains:
#define AUTHOR "Frank B. Brokken (f.b.brokken@rug.nl)";
SEE ALSO
ccache(1), icmake(1), icmbuild(1), icmstart(1), icmstart.rc(7).
BUGS
icmbuild(1) ends, displaying a fatal error message, if the current working directory does not contain a
file icmconf.
COPYRIGHT
This is free software, distributed under the terms of the GNU General Public License (GPL).
AUTHOR
Frank B. Brokken (f.b.brokken@rug.nl).
icmake.12.03.00 1992-2024 icmconf(7)