1CFLOW(1P) POSIX Programmer's Manual CFLOW(1P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 cflow — generate a C-language flowgraph (DEVELOPMENT)
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15 cflow [-r] [-d num] [-D name[=def]]... [-i incl] [-I dir]...
16 [-U dir]... file...
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19 The cflow utility shall analyze a collection of object files or assem‐
20 bler, C-language, lex, or yacc source files, and attempt to build a
21 graph, written to standard output, charting the external references.
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24 The cflow utility shall conform to the Base Definitions volume of
25 POSIX.1‐2017, Section 12.2, Utility Syntax Guidelines, except that the
26 order of the -D, -I, and -U options (which are identical to their
27 interpretation by c99) is significant.
28 The following options shall be supported:
30 -d num Indicate the depth at which the flowgraph is cut off. The
32 application shall ensure that the argument num is a decimal
33 integer. By default this is a very large number (typically
34 greater than 32000). Attempts to set the cut-off depth to a
35 non-positive integer shall be ignored.
36 -i incl Increase the number of included symbols. The incl option-
38 argument is one of the following characters:
39 x Include external and static data symbols. The default
41 shall be to include only functions in the flowgraph.
42 _ (Underscore) Include names that begin with an <under‐
44 score>. The default shall be to exclude these func‐
45 tions (and data if -i x is used).
46 -r Reverse the caller:callee relationship, producing an inverted
48 listing showing the callers of each function. The listing
49 shall also be sorted in lexicographical order by callee.
50
52 The following operand is supported:
53 file The pathname of a file for which a graph is to be generated.
55 Filenames suffixed by .l shall shall be taken to be lex
56 input, .y as yacc input, .c as c99 input, and .i as the out‐
57 put of c99 -E. Such files shall be processed as appropriate,
58 determined by their suffix.
59 Files suffixed by .s (conventionally assembler source) may
61 have more limited information extracted from them.
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64 Not used.
65
67 The input files shall be object files or assembler, C-language, lex, or
68 yacc source files.
69
71 The following environment variables shall affect the execution of
72 cflow:
73 LANG Provide a default value for the internationalization vari‐
75 ables that are unset or null. (See the Base Definitions vol‐
76 ume of POSIX.1‐2017, Section 8.2, Internationalization Vari‐
77 ables for the precedence of internationalization variables
78 used to determine the values of locale categories.)
79 LC_ALL If set to a non-empty string value, override the values of
81 all the other internationalization variables.
82 LC_COLLATE
84 Determine the locale for the ordering of the output when the
85 -r option is used.
86 LC_CTYPE Determine the locale for the interpretation of sequences of
88 bytes of text data as characters (for example, single-byte as
89 opposed to multi-byte characters in arguments and input
90 files).
91 LC_MESSAGES
93 Determine the locale that should be used to affect the format
94 and contents of diagnostic messages written to standard
95 error.
96 NLSPATH Determine the location of message catalogs for the processing
98 of LC_MESSAGES.
99
101 Default.
102
104 The flowgraph written to standard output shall be formatted as follows:
105 "%d %s:%s\n", <reference number>, <global>, <definition>
108 Each line of output begins with a reference (that is, line) number,
110 followed by indentation of at least one column position per level.
111 This is followed by the name of the global, a <colon>, and its defini‐
112 tion. Normally globals are only functions not defined as an external or
113 beginning with an <underscore>; see the OPTIONS section for the -i
114 inclusion option. For information extracted from C-language source, the
115 definition consists of an abstract type declaration (for example, char
116 *) and, delimited by angle brackets, the name of the source file and
117 the line number where the definition was found. Definitions extracted
118 from object files indicate the filename and location counter under
119 which the symbol appeared (for example, text).
120 Once a definition of a name has been written, subsequent references to
122 that name contain only the reference number of the line where the defi‐
123 nition can be found. For undefined references, only "<>" shall be writ‐
124 ten.
125
127 The standard error shall be used only for diagnostic messages.
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130 None.
131
133 None.
134
136 The following exit values shall be returned:
137 0 Successful completion.
139 >0 An error occurred.
141
143 Default.
144 The following sections are informative.
146
148 Files produced by lex and yacc cause the reordering of line number dec‐
149 larations, and this can confuse cflow. To obtain proper results, the
150 input of yacc or lex must be directed to cflow.
151
153 Given the following in file.c:
154 int i;
157 int f();
158 int g();
159 int h();
160 int
161 main()
162 {
163 f();
164 g();
165 f();
166 }
167 int
168 f()
169 {
170 i = h();
171 }
172 The command:
174 cflow -i x file.c
177 produces the output:
179 1 main: int(), <file.c 6>
182 2 f: int(), <file.c 13>
183 3 h: <>
184 4 i: int, <file.c 1>
185 5 g: <>
186
188 None.
189
191 None.
192
194 c99, lex, yacc
195 The Base Definitions volume of POSIX.1‐2017, Chapter 8, Environment
197 Variables, Section 12.2, Utility Syntax Guidelines
198
200 Portions of this text are reprinted and reproduced in electronic form
201 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
202 table Operating System Interface (POSIX), The Open Group Base Specifi‐
203 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
204 Electrical and Electronics Engineers, Inc and The Open Group. In the
205 event of any discrepancy between this version and the original IEEE and
206 The Open Group Standard, the original IEEE and The Open Group Standard
207 is the referee document. The original Standard can be obtained online
208 at http://www.opengroup.org/unix/online.html .
209 Any typographical or formatting errors that appear in this page are
211 most likely to have been introduced during the conversion of the source
212 files to man page format. To report such errors, see https://www.ker‐
213 nel.org/doc/man-pages/reporting_bugs.html .
214IEEE/The Open Group 2017 CFLOW(1P)