www.LinuxHowtos.org
CFLOW
Section: POSIX Programmer's Manual (1P)Updated: 2013
Index Return to Main Contents
PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.NAME
cflow --- generate a C-language flowgraph (DEVELOPMENT)SYNOPSIS
cflow [-r] [-d num] [-D name[=def]]... [-i incl] [-I dir]...
[-U dir]... file...
DESCRIPTION
The cflow utility shall analyze a collection of object files or assembler, C-language, lex, or yacc source files, and attempt to build a graph, written to standard output, charting the external references.OPTIONS
The cflow utility shall conform to the Base Definitions volume of POSIX.1-2008, Section 12.2, Utility Syntax Guidelines, except that the order of the -D, -I, and -U options (which are identical to their interpretation by c99) is significant. The following options shall be supported:- -d num
- Indicate the depth at which the flowgraph is cut off. The application shall ensure that the argument num is a decimal integer. By default this is a very large number (typically greater than 32000). Attempts to set the cut-off depth to a non-positive integer shall be ignored.
- -i incl
-
Increase the number of included symbols. The
incl
option-argument is one of the following characters:
-
- x
- Include external and static data symbols. The default shall be to include only functions in the flowgraph.
- _
- (Underscore) Include names that begin with an <underscore>. The default shall be to exclude these functions (and data if -i x is used).
-
- -r
- Reverse the caller:callee relationship, producing an inverted listing showing the callers of each function. The listing shall also be sorted in lexicographical order by callee.
OPERANDS
The following operand is supported:- file
-
The pathname of a file for which a graph is to be generated.
Filenames suffixed by
.l
shall shall be taken to be
lex
input,
.y
as
yacc
input,
.c
as
c99
input, and
.i
as the output of
c99
-E.
Such files shall be processed as appropriate, determined by their
suffix.
-
Files suffixed by .s (conventionally assembler source) may have more limited information extracted from them.
-
STDIN
Not used.INPUT FILES
The input files shall be object files or assembler, C-language, lex, or yacc source files.ENVIRONMENT VARIABLES
The following environment variables shall affect the execution of cflow:- LANG
- Provide a default value for the internationalization variables that are unset or null. (See the Base Definitions volume of POSIX.1-2008, Section 8.2, Internationalization Variables for the precedence of internationalization variables used to determine the values of locale categories.)
- LC_ALL
- If set to a non-empty string value, override the values of all the other internationalization variables.
- LC_COLLATE
-
Determine the locale for the ordering of the output when the -r option is used. - LC_CTYPE
- Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single-byte as opposed to multi-byte characters in arguments and input files).
- LC_MESSAGES
-
Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error. - NLSPATH
- Determine the location of message catalogs for the processing of LC_MESSAGES.
ASYNCHRONOUS EVENTS
Default.STDOUT
The flowgraph written to standard output shall be formatted as follows:
-
"%d %s:%s\n", <reference number>, <global>, <definition>
STDERR
The standard error shall be used only for diagnostic messages.OUTPUT FILES
None.EXTENDED DESCRIPTION
None.EXIT STATUS
The following exit values shall be returned:- 0
- Successful completion.
- >0
- An error occurred.
CONSEQUENCES OF ERRORS
Default.The following sections are informative.
APPLICATION USAGE
Files produced by lex and yacc cause the reordering of line number declarations, and this can confuse cflow. To obtain proper results, the input of yacc or lex must be directed to cflow.EXAMPLES
Given the following in file.c:
-
int i; int f(); int g(); int h(); int main() { f(); g(); f(); } int f() { i = h(); }
-
cflow -i x file.c
-
1 main: int(), <file.c 6> 2 f: int(), <file.c 13> 3 h: <> 4 i: int, <file.c 1> 5 g: <>
RATIONALE
None.FUTURE DIRECTIONS
None.SEE ALSO
c99, lex, yacc The Base Definitions volume of POSIX.1-2008, Chapter 8, Environment Variables, Section 12.2, Utility Syntax GuidelinesCOPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .