Provided by: cproto_4.7y-1_amd64 
NAME
cproto - generate C function prototypes and convert function definitions
SYNOPSIS
cproto [ option ... ] [ file ... ]
DESCRIPTION
Extracting
Cproto generates function prototypes for functions defined in the specified C source files to the
standard output. The function definitions may be in the old style or ANSI C style. Optionally, cproto
also outputs declarations for variables defined in the files. If no file argument is given, cproto reads
its input from the standard input.
Converting ANSI C
Cproto can convert function definitions in simple source files from the old style to the ANSI C style
(see BUGS for limitations). The original source files along with files specified by
#include "file"
directives appearing in the source code will be overwritten with the converted code. If no file names
are given on the command line, then the program reads the source code from the standard input and outputs
the converted source to the standard output.
If any comments appear in the parameter declarations for a function definition, such as in the example,
main (argc, argv)
int argc; /* number of arguments */
char *argv[]; /* arguments */
{
}
then the converted function definition will have the form
int
main (
int argc, /* number of arguments */
char *argv[] /* arguments */
)
{
}
Otherwise, the converted function definition will look like
int
main (int argc, char *argv[])
{
}
Converting K&R C
Cproto can convert function definitions from the ANSI style to the old K&R style. In this mode, the
program also converts function declarators and prototypes that appear outside function bodies. This is
not a complete ANSI C to old C conversion. The program does not change anything within function bodies.
Lint-libraries
Cproto can optionally generate source in lint-library format. This is useful in environments where the
lint utility is used to supplement prototype checking of your program.
OPTIONS
-a Convert function definitions from the old style to the ANSI C style.
-B directive
Set the conditional compilation directive to output at the beginning of function definitions
generated by the -b option. The default is
#ifdef ANSI_FUNC
-b Rewrite function definition heads to include both old style and new style declarations separated
by a conditional compilation directive. For example, the program can generate this function
definition:
#ifdef ANSI_FUNC
int
main (int argc, char *argv[])
#else
int
main (argc, argv)
int argc;
char *argv[]
#endif
{
}
-C template
Set the output format for function definitions with parameter comments. The -F and -P options
allow setting the format for prototypes and function definitions.
The format is specified by a template in the form
" int f ( a, b )"
but you may replace each space in this string with any number of whitespace characters. For
example, the option
-F"int f(\n\ta,\n\tb\n\t)"
will produce
int main(
int argc,
char *argv[]
)
-c The parameter comments in the prototypes generated by the -f1 and -f2 options are omitted by
default. Use this option to enable the output of these comments.
-D name[=value]
This option is passed through to the preprocessor and is used to define symbols for use with
conditionals such as #ifdef.
-d Omit the definition of the prototype macro used by the -m option.
-E cpp Pipe the input files through the specified C preprocessor command when generating prototypes. By
default, the program uses “gcc -E” via a pipe.
-E 0 Do not run the C preprocessor.
-e Output the keyword extern in front of every generated prototype or declaration that has global
scope.
-F template
Set the output format for function definitions as in the “-C” option.
-f n Set the style of generated function prototypes where n is a number from 0 to 3. For example,
consider the function definition
main (argc, argv)
int argc;
char *argv[];
{
}
If the value is 0, then no prototypes are generated. When set to 1, the output is:
int main(/*int argc, char *argv[]*/);
For a value of 2, the output has the form:
int main(int /*argc*/, char */*argv*/[]);
The default value is 3. It produces the full function prototype:
int main(int argc, char *argv[]);
-I directory
This option is passed through to the preprocessor and is used to specify a directory to search for
files that are referenced with #include.
-i By default, cproto only generates declarations for functions and variables having global scope.
This option will output inline declarations as well.
-l Generate text for a lint-library (overrides the “-f” option). The output includes the comment
/* LINTLIBRARY */
Special comments LINT_EXTERN and LINT_PREPRO (a la “VARARGS”) respectively turn on the “-x” option
and copy comment-text to the output (for preprocessing in lint). Use the comment
/* LINT_EXTERN2 */
to include externs defined in the first level of include-files. Use the comment
/* LINT_SHADOWED */
to cause cproto to put “#undef” directives before each lint library declaration (i.e., to avoid
conflicts with macros that happen to have to have the same name as the functions, thus causing
syntax errors).
Note that these special comments are not supported under VAX/VMS, since there is no equivalent for
the “-C” option of the C preprocessor with VAX-C.
-M name
Set the name of the macro used to surround prototype parameter lists when option -m is selected.
The default is “P_”.
-m Put a macro around the parameter list of every generated prototype. For example:
int main P_((int argc, char *argv[]));
-N name
Rather than filling in “void” for functions without parameters, use the given name.
-n Rather than filling in “void” for functions without parameters, use a comment “/*empty*/”.
-O file
Specify the name of the error file (default: standard error).
-o file
Specify the name of the output file (default: standard output).
-P template
Set the output format for generated prototypes as in the “-C” option.
-p Disable promotion of formal parameters in old style function definitions. By default, parameters
of type char or short in old style function definitions are promoted to type int in the function
prototype or converted ANSI C function definition. Parameters of type float get promoted to
double as well.
-q Do not output any error messages when the program cannot read the file specified in an #include
directive.
-S Output only static declarations.
-s By default, cproto only generates declarations for functions and variables having global scope.
This option will output static declarations as well.
-T Copy type definitions from each file. (Definitions in included-files are copied, unlike the “-l”
option).
-t Convert function definitions from the ANSI C style to the traditional style.
-U name
This option is passed through to the preprocessor and is used to remove any definitions of this
symbol.
-V Print version information.
-v Also output declarations for variables defined in the source.
-X level
This option limits the include-file level from which declarations are extracted by examining the
preprocessor output.
-x This option causes procedures and variables which are declared “extern” to be included in the
output.
ENVIRONMENT
The environment variable CPROTO is scanned for a list of options in the same format as the command line
options. Options given on the command line override any corresponding environment option.
BUGS
If an un-tagged struct, union or enum declaration appears in a generated function prototype or converted
function definition, the content of the declaration between the braces is empty.
The program does not pipe the source files through the C preprocessor when it is converting function
definitions (i.e., options -a, -b, -t). That is because cproto does the conversion by replacing strings,
rather than by converting to/from lexical tokens. Instead of using the C preprocessor, cproto tries to
handle preprocessor directives and macros itself, to find type definitions. There are several
limitations as a result:
• the search-path for included files contains only “/usr/include” and the directories listed by “-I”
options.
• conditional directives (e.g., “#if”) are ignored.
• only macros without parameters are handled.
• some comments in the function definition head are discarded.
The -v option does not generate declarations for variables defined with the extern specifier. This does
not strictly conform to the C language standard but this rule was implemented because include files
commonly declare variables this way.
When the program encounters an error, it usually outputs the not very descriptive message “syntax error”.
(Your configuration may allow the extended error reporting in yyerror.c).
Options that take string arguments only interpret the following character escape sequences:
\n newline
\s space
\t tab
VARARGS comments are not passed through on systems whose C preprocessors do not support this (e.g.,
VAX/VMS, MS-DOS).
AUTHORS
Chin Huang
cthuang@vex.net
cthuang@interlog.com
Thomas E. Dickey
dickey@invisible-island.net
modifications to support lint library, type-copying, and port to VAX/VMS.
SEE ALSO
cc(1), cpp(1)
Version 4.7y 2025-09-01 CPROTO(1)