[unix-history] / usr / man / man1 / lint.1

.TH LINT 1 
.SH NAME
lint \- a C program verifier
.SH SYNOPSIS
.B lint
[
.B \-abchnpuvx
]
file ...
.SH DESCRIPTION
.I Lint
attempts to detect features of the C program
.I files
which are
likely to be bugs, or non-portable, or wasteful.
It also checks the type usage of the program more strictly
than the compilers.
Among the things which are currently found are
unreachable statements,
loops not entered at the top,
automatic variables declared and not used,
and logical expressions whose value is constant.
Moreover, the usage of functions is checked to find
functions which return values in some places and not in others,
functions called with varying numbers of arguments,
and functions whose values are not used.
.PP
By default, it is assumed that all the
.I files
are to be loaded together; they are checked for
mutual compatibility.
Function definitions for certain libraries are available to
.IR lint ;
these libraries are referred to by a
conventional name,
such as `-lm', in the style of
.IR ld (1).
.PP
Any number of the options in the following list
may be used.
The
.SM
.BR \-D "\*S,"
.SM
.BR \-U "\*S,"
and
.SM
.B \-I
options of
.IR cc (1)
are also recognized as separate arguments.
.TP
.B p
Attempt to check portability to the
.I IBM
and
.I GCOS
dialects of C.
.TP
.B h
Apply a number of heuristic tests to attempt to
intuit bugs, improve style, and reduce waste.
.TP
.B b
Report
.I break
statements that cannot be reached.
(This is not the default because, unfortunately,
most
.I lex
and many
.I yacc
outputs produce dozens of such comments.)
.TP
.B v
Suppress complaints about unused arguments in functions.
.TP
.B x
Report variables referred to by extern declarations,
but never used.
.TP
.B a
Report assignments of long values to int variables.
.TP
.B c
Complain about casts which have questionable portability.
.TP
.B u
Do not complain about functions and variables used and not
defined, or defined and not used (this is suitable for running
.I lint
on a subset of files out of a larger program).
.TP
.B n
Do not check compatibility against the standard library.
.PP
.IR Exit (2)
and other functions which do not return
are not understood; this causes various lies.
.PP
Certain conventional comments in the C source
will change the behavior of
.IR lint :
.TP
/*NOTREACHED*/
at appropriate points
stops comments about unreachable code.
.TP
.RI /*VARARGS n */
suppresses
the usual checking for variable numbers of arguments
in the following function declaration.
The data types of the first
.I n
arguments are checked;
a missing
.I n
is taken to be 0.
.TP
/*NOSTRICT*/
shuts off strict type checking in the next expression.
.TP
/*ARGSUSED*/
turns on the
.B \-v
option for the next function.
.TP
/*LINTLIBRARY*/
at the beginning of a file shuts off complaints about
unused functions in this file.
.SH FILES
.ta \w'/usr/lib/llib-port  'u
/usr/lib/lint[12] programs
.br
/usr/lib/llib-lc declarations for standard functions
.br
/usr/lib/llib-port declarations for portable functions
.SH SEE ALSO
cc(1)
.br
S. C. Johnson,
.I Lint, a C Program Checker
Commit	Line	Data
e6817382 BJ	1	.TH LINT 1
	2	.SH NAME
	3	lint \- a C program verifier
	4	.SH SYNOPSIS
	5	.B lint
	6	[
	7	.B \-abchnpuvx
	8	]
	9	file ...
	10	.SH DESCRIPTION
	11	.I Lint
	12	attempts to detect features of the C program
	13	.I files
	14	which are
	15	likely to be bugs, or non-portable, or wasteful.
	16	It also checks the type usage of the program more strictly
	17	than the compilers.
	18	Among the things which are currently found are
	19	unreachable statements,
	20	loops not entered at the top,
	21	automatic variables declared and not used,
	22	and logical expressions whose value is constant.
	23	Moreover, the usage of functions is checked to find
	24	functions which return values in some places and not in others,
	25	functions called with varying numbers of arguments,
	26	and functions whose values are not used.
	27	.PP
	28	By default, it is assumed that all the
	29	.I files
	30	are to be loaded together; they are checked for
	31	mutual compatibility.
	32	Function definitions for certain libraries are available to
	33	.IR lint ;
	34	these libraries are referred to by a
	35	conventional name,
	36	such as `-lm', in the style of
	37	.IR ld (1).
	38	.PP
	39	Any number of the options in the following list
	40	may be used.
	41	The
	42	.SM
	43	.BR \-D "\*S,"
	44	.SM
	45	.BR \-U "\*S,"
	46	and
	47	.SM
	48	.B \-I
	49	options of
	50	.IR cc (1)
	51	are also recognized as separate arguments.
	52	.TP
	53	.B p
	54	Attempt to check portability to the
	55	.I IBM
	56	and
	57	.I GCOS
	58	dialects of C.
	59	.TP
	60	.B h
	61	Apply a number of heuristic tests to attempt to
	62	intuit bugs, improve style, and reduce waste.
	63	.TP
	64	.B b
65	Report
66	.I break
67	statements that cannot be reached.
68	(This is not the default because, unfortunately,
69	most
70	.I lex
71	and many
72	.I yacc
73	outputs produce dozens of such comments.)
74	.TP
75	.B v
76	Suppress complaints about unused arguments in functions.
77	.TP
78	.B x
79	Report variables referred to by extern declarations,
80	but never used.
81	.TP
82	.B a
83	Report assignments of long values to int variables.
84	.TP
85	.B c
86	Complain about casts which have questionable portability.
87	.TP
88	.B u
89	Do not complain about functions and variables used and not
90	defined, or defined and not used (this is suitable for running
91	.I lint
92	on a subset of files out of a larger program).
93	.TP
94	.B n
95	Do not check compatibility against the standard library.
96	.PP
97	.IR Exit (2)
98	and other functions which do not return
99	are not understood; this causes various lies.
100	.PP
101	Certain conventional comments in the C source
102	will change the behavior of
103	.IR lint :
104	.TP
105	/NOTREACHED/
106	at appropriate points
107	stops comments about unreachable code.
108	.TP
109	.RI /VARARGS n /
110	suppresses
111	the usual checking for variable numbers of arguments
112	in the following function declaration.
113	The data types of the first
114	.I n
115	arguments are checked;
116	a missing
117	.I n
118	is taken to be 0.
119	.TP
120	/NOSTRICT/
121	shuts off strict type checking in the next expression.
122	.TP
123	/ARGSUSED/
124	turns on the
125	.B \-v
126	option for the next function.
127	.TP
128	/LINTLIBRARY/
129	at the beginning of a file shuts off complaints about
130	unused functions in this file.
131	.SH FILES
132	.ta \w'/usr/lib/llib-port 'u
133	/usr/lib/lint[12] programs
134	.br
135	/usr/lib/llib-lc declarations for standard functions
136	.br
137	/usr/lib/llib-port declarations for portable functions
138	.SH SEE ALSO
139	cc(1)
140	.br
141	S. C. Johnson,
142	.I Lint, a C Program Checker