cflow(1)
cflow --
generate C flowgraph
Synopsis
cflow [-c] [-r] [-ix] [-i_] [-dnum] -V files
Description
The cflow command analyzes a collection of C,
yacc, lex, assembler, and object files
and builds a graph charting the external function references.
Files suffixed with .y, .l, and .c
are processed by yacc, lex, and the C compiler as appropriate.
The results of the preprocessed files,
and files suffixed with .i,
are then run through the first pass of lint.
Files suffixed with .s are assembled.
Assembled files, and files suffixed with
.o, have information extracted from their symbol tables.
The results are collected and turned into a graph of external references
that is written on the standard output.
When used with the -c option cflow produces an intermediate
.cf file which can be given to cflow as input for further
processing.
cflow processes supplementary code
set characters in literals and constants
according to the locale specified in the LC_CTYPE
environment variable [see LANG on
environ(5)].
Each line of output begins with a reference
number, followed by a suitable number of tabs
indicating the level,
then the name of the global symbol
followed by a colon
and its definition.
Normally only function names that do not begin with
an underscore are listed (see the
-i
options below).
For information extracted from C source,
the definition consists of an abstract type declaration
(for example,
char
),
and, delimited by angle brackets,
the name of the source file
and the line number
where the definition was found.
Definitions extracted from object files
indicate the file name and location
counter under which the symbol appeared
(for example,
text).
If the compilation system adds a leading underscore to external names,
it is removed.
Once a definition of a name has been printed,
subsequent references to that name contain
only the reference number of the line
where the definition may be found.
For undefined references, only
``<>''
is printed.
As an example, suppose the following code is in
file.c:
int i;
main()
{
f();
g();
f();
}
f()
{
i = h();
}
The command
cflow -ix file.c
produces the output
1 main: int(), <file.c 4>
2 f: int(), <file.c 11>
3 h: <>
4 i: int, <file.c 1>
5 g: <>
When the nesting level becomes too deep, the output of
cflow can be piped to the pr command,
using the -e option, to compress the tab expansion to something
less than every eight spaces.
In addition to the -D, -I, -Kdollar
and -U
options (which are interpreted just as they are
by cc), the following options are interpreted by
cflow:
-r-
Reverse the ``caller:callee'' relationship producing an inverted listing
showing the callers of each function.
The listing is also sorted in
lexicographical order by callee.
-ix-
Include external and static data symbols.
The default is to include
only functions in the flowgraph.
-i_-
Include names that begin with an underscore.
The default is to exclude
these functions (and data if -ix is used).
-dnum-
The num
decimal integer indicates the depth at which the flowgraph
is cut off.
By default this number is very large.
Attempts to set
the cutoff depth to a nonpositive integer will be ignored.
-V-
Prints version information on the standard error output.
Errors
Complains about multiple definitions and only believes the first.
References
as(1),
cc(1),
lex(1),
lint(1),
nm(1),
yacc(1)
Notices
Files produced by lex and
yacc cause the reordering of line number declarations, which can
confuse cflow.
To get proper results, feed cflow the yacc
or lex input.
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 25 April 2004