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

.TH LINT 1
.UC 4
.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/lint[12] programs
.br
/usr/lib/lint/llib-lc declarations for standard functions
.br
/usr/lib/lint/llib-port declarations for portable functions
.SH SEE ALSO
cc(1)
.br
S. C. Johnson,
.I Lint, a C Program Checker
.SH BUGS
There are some things you just
.B can't
get lint to shut up about.
Commit	Line	Data
e3758c96 C	1	.TH LINT 1
	2	.UC 4
	3	.SH NAME
	4	lint \- a C program verifier
	5	.SH SYNOPSIS
	6	.B lint
	7	[
	8	.B \-abchnpuvx
	9	]
	10	file ...
	11	.SH DESCRIPTION
	12	.I Lint
	13	attempts to detect features of the C program
	14	.I files
	15	which are
	16	likely to be bugs, or non-portable, or wasteful.
	17	It also checks the type usage of the program more strictly
	18	than the compilers.
	19	Among the things which are currently found are
	20	unreachable statements,
	21	loops not entered at the top,
	22	automatic variables declared and not used,
	23	and logical expressions whose value is constant.
	24	Moreover, the usage of functions is checked to find
	25	functions which return values in some places and not in others,
	26	functions called with varying numbers of arguments,
	27	and functions whose values are not used.
	28	.PP
	29	By default, it is assumed that all the
	30	.I files
	31	are to be loaded together; they are checked for
	32	mutual compatibility.
	33	Function definitions for certain libraries are available to
	34	.IR lint ;
	35	these libraries are referred to by a
	36	conventional name,
	37	such as `\-lm', in the style of
	38	.IR ld (1).
	39	.PP
	40	Any number of the options in the following list
	41	may be used.
	42	The
	43	.SM
	44	.BR \-D "\*S,"
	45	.SM
	46	.BR \-U "\*S,"
	47	and
	48	.SM
	49	.B \-I
	50	options of
	51	.IR cc (1)
	52	are also recognized as separate arguments.
	53	.TP
	54	.B p
	55	Attempt to check portability to the
	56	.I IBM
	57	and
	58	.I GCOS
	59	dialects of C.
	60	.TP
	61	.B h
	62	Apply a number of heuristic tests to attempt to
	63	intuit bugs, improve style, and reduce waste.
	64	.TP
65	.B b
66	Report
67	.I break
68	statements that cannot be reached.
69	(This is not the default because, unfortunately,
70	most
71	.I lex
72	and many
73	.I yacc
74	outputs produce dozens of such comments.)
75	.TP
76	.B v
77	Suppress complaints about unused arguments in functions.
78	.TP
79	.B x
80	Report variables referred to by extern declarations,
81	but never used.
82	.TP
83	.B a
84	Report assignments of long values to int variables.
85	.TP
86	.B c
87	Complain about casts which have questionable portability.
88	.TP
89	.B u
90	Do not complain about functions and variables used and not
91	defined, or defined and not used (this is suitable for running
92	.I lint
93	on a subset of files out of a larger program).
94	.TP
95	.B n
96	Do not check compatibility against the standard library.
97	.PP
98	.IR Exit (2)
99	and other functions which do not return
100	are not understood; this causes various lies.
101	.PP
102	Certain conventional comments in the C source
103	will change the behavior of
104	.IR lint :
105	.TP
106	/NOTREACHED/
107	at appropriate points
108	stops comments about unreachable code.
109	.TP
110	.RI /VARARGS n /
111	suppresses
112	the usual checking for variable numbers of arguments
113	in the following function declaration.
114	The data types of the first
115	.I n
116	arguments are checked;
117	a missing
118	.I n
119	is taken to be 0.
120	.TP
121	/NOSTRICT/
122	shuts off strict type checking in the next expression.
123	.TP
124	/ARGSUSED/
125	turns on the
126	.B \-v
127	option for the next function.
128	.TP
129	/LINTLIBRARY/
130	at the beginning of a file shuts off complaints about
131	unused functions in this file.
132	.SH FILES
133	.ta \w'/usr/lib/llib-port 'u
134	/usr/lib/lint/lint[12] programs
135	.br
136	/usr/lib/lint/llib-lc declarations for standard functions
137	.br
138	/usr/lib/lint/llib-port declarations for portable functions
139	.SH SEE ALSO
140	cc(1)
141	.br
142	S. C. Johnson,
143	.I Lint, a C Program Checker
144	.SH BUGS
145	There are some things you just
146	.B can't
147	get lint to shut up about.