.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "CFLOW" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" cflow 
.SH 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.
.SH NAME
cflow \- generate a C-language flowgraph (\fBDEVELOPMENT\fP)
.SH SYNOPSIS
.LP
\fBcflow\fP \fB[\fP\fB-r\fP\fB][\fP\fB-d\fP \fInum\fP\fB][\fP\fB-D\fP
\fIname\fP\fB[\fP\fB=\fP\fIdef\fP\fB]]\fP \fB...\fP \fB[\fP\fB-i\fP
\fIincl\fP\fB][\fP\fB-I\fP
\fIdir\fP\fB]\fP \fB...
.br
\ \ \ \ \ \ \fP \fB[\fP\fB-U\fP \fIdir\fP\fB]\fP \fB...\fP \fIfile\fP
\fB\&... \fP
.SH DESCRIPTION
.LP
The \fIcflow\fP utility shall analyze a collection of object files
or assembler, C-language, \fIlex\fP, or \fIyacc\fP source files, and
attempt to build a
graph, written to standard output, charting the external references.
.SH OPTIONS
.LP
The \fIcflow\fP utility shall conform to the Base Definitions volume
of IEEE\ Std\ 1003.1-2001, Section 12.2, Utility Syntax Guidelines,
except that the order of the \fB-D\fP,
\fB-I\fP, and \fB-U\fP options (which are identical to their interpretation
by \fIc99\fP) is
significant.
.LP
The following options shall be supported:
.TP 7
\fB-d\ \fP \fInum\fP
Indicate the depth at which the flowgraph is cut off. The application
shall ensure that the argument \fInum\fP 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.
.TP 7
\fB-i\ \fP \fIincl\fP
Increase the number of included symbols. The \fIincl\fP option-argument
is one of the following characters: 
.TP 7
\fIx\fP
.RS
Include external and static data symbols. The default shall be to
include only functions in the flowgraph.
.RE
.TP 7
\fB_\fP
.RS
(Underscore) Include names that begin with an underscore. The default
shall be to exclude these functions (and data if
\fB-i\ x\fP is used).
.RE
.sp
.TP 7
\fB-r\fP
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.
.sp
.SH OPERANDS
.LP
The following operand is supported:
.TP 7
\fIfile\fP
The pathname of a file for which a graph is to be generated. Filenames
suffixed by \fB.l\fP shall shall be taken to be \fIlex\fP input, \fB.y\fP
as \fIyacc\fP input, \fB.c\fP
as \fIc99\fP input, and \fB.i\fP as the output of \fIc99\fP \fB-E\fP.
Such files shall be processed as appropriate, determined by their
suffix. 
.LP
Files suffixed by \fB.s\fP (conventionally assembler source) may have
more limited information extracted from them.
.sp
.SH STDIN
.LP
Not used.
.SH INPUT FILES
.LP
The input files shall be object files or assembler, C-language, \fIlex\fP,
or \fIyacc\fP source files.
.SH ENVIRONMENT VARIABLES
.LP
The following environment variables shall affect the execution of
\fIcflow\fP:
.TP 7
\fILANG\fP
Provide a default value for the internationalization variables that
are unset or null. (See the Base Definitions volume of
IEEE\ Std\ 1003.1-2001, Section 8.2, Internationalization Variables
for
the precedence of internationalization variables used to determine
the values of locale categories.)
.TP 7
\fILC_ALL\fP
If set to a non-empty string value, override the values of all the
other internationalization variables.
.TP 7
\fILC_COLLATE\fP
.sp
Determine the locale for the ordering of the output when the \fB-r\fP
option is used.
.TP 7
\fILC_CTYPE\fP
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).
.TP 7
\fILC_MESSAGES\fP
Determine the locale that should be used to affect the format and
contents of diagnostic messages written to standard
error.
.TP 7
\fINLSPATH\fP
Determine the location of message catalogs for the processing of \fILC_MESSAGES
\&.\fP
.sp
.SH ASYNCHRONOUS EVENTS
.LP
Default.
.SH STDOUT
.LP
The flowgraph written to standard output shall be formatted as follows:
.sp
.RS
.nf

\fB"%d %s:%s\\n", <\fP\fIreference number\fP\fB>, <\fP\fIglobal\fP\fB>, <\fP\fIdefinition\fP\fB>
\fP
.fi
.RE
.LP
Each line of output begins with a reference (that is, line) number,
followed by indentation of at least one column position per
level. This is followed by the name of the global, a colon, and its
definition. Normally globals are only functions not defined as
an external or beginning with an underscore; see the OPTIONS section
for the \fB-i\fP inclusion option. For information extracted
from C-language source, the definition consists of an abstract type
declaration (for example, \fBchar *\fP) 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 filename and location counter under which the symbol
appeared (for example, \fItext\fP).
.LP
Once a definition of a name has been written, subsequent references
to that name contain only the reference number of the line
where the definition can be found. For undefined references, only
\fB"<>"\fP shall be written.
.SH STDERR
.LP
The standard error shall be used only for diagnostic messages.
.SH OUTPUT FILES
.LP
None.
.SH EXTENDED DESCRIPTION
.LP
None.
.SH EXIT STATUS
.LP
The following exit values shall be returned:
.TP 7
\ 0
Successful completion.
.TP 7
>0
An error occurred.
.sp
.SH CONSEQUENCES OF ERRORS
.LP
Default.
.LP
\fIThe following sections are informative.\fP
.SH APPLICATION USAGE
.LP
Files produced by \fIlex\fP and \fIyacc\fP cause the
reordering of line number declarations, and this can confuse \fIcflow\fP.
To obtain proper results, the input of \fIyacc\fP or \fIlex\fP must
be directed to \fIcflow\fP.
.SH EXAMPLES
.LP
Given the following in \fBfile.c\fP:
.sp
.RS
.nf

\fBint i;
int f();
int g();
int h();
int
main()
{
    f();
    g();
    f();
}
int
f()
{
    i = h();
}
\fP
.fi
.RE
.LP
The command:
.sp
.RS
.nf

\fBcflow -i x file.c
\fP
.fi
.RE
.LP
produces the output:
.sp
.RS
.nf

\fB1 main: int(), <file.c 6>
2    f: int(), <file.c 13>
3        h: <>
4        i: int, <file.c 1>
5    g: <>
\fP
.fi
.RE
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fIc99\fP, \fIlex\fP, \fIyacc\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .
