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<HTML><HEAD><TITLE>Manpage of IPSEC_ATOUL</TITLE>
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<H1>IPSEC_ATOUL</H1>
Section: C Library Functions (3)<BR>Updated: 11 June 2001<BR><A HREF="#index">Index</A>
<A HREF="http://localhost/cgi-bin/man/man2html">Return to Main Contents</A><HR>


<A NAME="lbAB">&nbsp;</A>
<H2>NAME</H2>

ipsec atoul, ultoa - convert unsigned-long numbers to and from ASCII
<A NAME="lbAC">&nbsp;</A>
<H2>SYNOPSIS</H2>

<B>#include &lt;<A HREF="file:/usr/include/freeswan.h">freeswan.h</A>&gt;</B>

<P>
<B>const char *atoul(const char *src, size_t srclen,</B>

<BR>
&nbsp;
<B>int base, unsigned long *n);</B>

<BR>

<B>size_t ultoa(unsigned long n, int base, char *dst,</B>

<BR>
&nbsp;
<B>size_t dstlen);</B>

<A NAME="lbAD">&nbsp;</A>
<H2>DESCRIPTION</H2>

These functions are obsolete; see
<I><A HREF="ipsec_ttoul.3.html">ipsec_ttoul</A></I>(3)

for their replacements.
<P>

<I>Atoul</I>

converts an ASCII number into a binary
<B>unsigned long</B>

value.
<I>Ultoa</I>

does the reverse conversion, back to an ASCII version.
<P>

Numbers are specified in ASCII as
decimal (e.g.
<B>123</B>),

octal with a leading zero (e.g.
<B>012</B>,

which has value 10),
or hexadecimal with a leading
<B>0x</B>

(e.g.
<B>0x1f</B>,

which has value 31)
in either upper or lower case.
<P>

The
<I>srclen</I>

parameter of
<I>atoul</I>

specifies the length of the ASCII string pointed to by
<I>src</I>;

it is an error for there to be anything else
(e.g., a terminating NUL) within that length.
As a convenience for cases where an entire NUL-terminated string is
to be converted,
a
<I>srclen</I>

value of
<B>0</B>

is taken to mean
<B>strlen(src)</B>.

<P>

The
<I>base</I>

parameter of
<I>atoul</I>

can be
<B>8</B>,

<B>10</B>,

or
<B>16</B>,

in which case the number supplied is assumed to be of that form
(and in the case of
<B>16</B>,

to lack any
<B>0x</B>

prefix).
It can also be
<B>0</B>,

in which case the number is examined for a leading zero
or a leading
<B>0x</B>

to determine its base,
or
<B>13</B>

(halfway between 10 and 16),
which has the same effect as
<B>0</B>

except that a non-hexadecimal
number is considered decimal regardless of any leading zero.
<P>

The
<I>dstlen</I>

parameter of
<I>ultoa</I>

specifies the size of the
<I>dst</I>

parameter;
under no circumstances are more than
<I>dstlen</I>

bytes written to
<I>dst</I>.

A result which will not fit is truncated.
<I>Dstlen</I>

can be zero, in which case
<I>dst</I>

need not be valid and no result is written,
but the return value is unaffected;
in all other cases, the (possibly truncated) result is NUL-terminated.
<P>

The
<I>base</I>

parameter of
<I>ultoa</I>

must be
<B>8</B>,

<B>10</B>,

or
<B>16</B>.

<P>

<I>Atoul</I>

returns NULL for success and
a pointer to a string-literal error message for failure;
see DIAGNOSTICS.
<I>Ultoa</I>

returns the size of buffer which would 
be needed to
accommodate the full conversion result, including terminating NUL;
it is the caller's responsibility to check this against the size of
the provided buffer to determine whether truncation has occurred.
<A NAME="lbAE">&nbsp;</A>
<H2>SEE ALSO</H2>

<A HREF="atol.3.html">atol</A>(3), <A HREF="strtoul.3.html">strtoul</A>(3)
<A NAME="lbAF">&nbsp;</A>
<H2>DIAGNOSTICS</H2>

Fatal errors in
<I>atoul</I>

are:
empty input;
unknown
<I>base</I>;

non-digit character found;
number too large for an
<B>unsigned long</B>.

<A NAME="lbAG">&nbsp;</A>
<H2>HISTORY</H2>

Written for the FreeS/WAN project by Henry Spencer.
<A NAME="lbAH">&nbsp;</A>
<H2>BUGS</H2>

There is no provision for reporting an invalid
<I>base</I>

parameter given to
<I>ultoa</I>.

<P>

The restriction of error reports to literal strings
(so that callers don't need to worry about freeing them or copying them)
does limit the precision of error reporting.
<P>

The error-reporting convention lends itself to slightly obscure code,
because many readers will not think of NULL as signifying success.
A good way to make it clearer is to write something like:
<P>

<DL COMPACT><DT><DD>
<PRE>
<B>const char *error;</B>

<B>error = atoul( /* ... */ );</B>
<B>if (error != NULL) {</B>
<B>        /* something went wrong */</B>
</PRE>

</DL>

<P>

<HR>
<A NAME="index">&nbsp;</A><H2>Index</H2>
<DL>
<DT><A HREF="#lbAB">NAME</A><DD>
<DT><A HREF="#lbAC">SYNOPSIS</A><DD>
<DT><A HREF="#lbAD">DESCRIPTION</A><DD>
<DT><A HREF="#lbAE">SEE ALSO</A><DD>
<DT><A HREF="#lbAF">DIAGNOSTICS</A><DD>
<DT><A HREF="#lbAG">HISTORY</A><DD>
<DT><A HREF="#lbAH">BUGS</A><DD>
</DL>
<HR>
This document was created by
<A HREF="http://localhost/cgi-bin/man/man2html">man2html</A>,
using the manual pages.<BR>
Time: 21:40:17 GMT, November 11, 2003
</BODY>
</HTML>
Commit	Line	Data
997358a6 MW	1	Content-type: text/html
	2
	3	<HTML><HEAD><TITLE>Manpage of IPSEC_ATOUL</TITLE>
	4	</HEAD><BODY>
	5	<H1>IPSEC_ATOUL</H1>
	6	Section: C Library Functions (3)<BR>Updated: 11 June 2001<BR><A HREF="#index">Index</A>
	7	<A HREF="http://localhost/cgi-bin/man/man2html">Return to Main Contents</A><HR>
	8
	9
	10	<A NAME="lbAB"> </A>
	11	<H2>NAME</H2>
	12
	13	ipsec atoul, ultoa - convert unsigned-long numbers to and from ASCII
	14	<A NAME="lbAC"> </A>
	15	<H2>SYNOPSIS</H2>
	16
	17	<B>#include <<A HREF="file:/usr/include/freeswan.h">freeswan.h</A>></B>
	18
	19	<P>
	20	<B>const char atoul(const char src, size_t srclen,</B>
	21
	22	<BR>
	23
	24	<B>int base, unsigned long *n);</B>
	25
	26	<BR>
	27
	28	<B>size_t ultoa(unsigned long n, int base, char *dst,</B>
	29
	30	<BR>
	31
	32	<B>size_t dstlen);</B>
	33
	34	<A NAME="lbAD"> </A>
	35	<H2>DESCRIPTION</H2>
	36
	37	These functions are obsolete; see
	38	<I><A HREF="ipsec_ttoul.3.html">ipsec_ttoul</A></I>(3)
	39
	40	for their replacements.
	41	<P>
	42
	43	<I>Atoul</I>
	44
	45	converts an ASCII number into a binary
	46	<B>unsigned long</B>
	47
	48	value.
	49	<I>Ultoa</I>
	50
	51	does the reverse conversion, back to an ASCII version.
	52	<P>
	53
	54	Numbers are specified in ASCII as
	55	decimal (e.g.
	56	<B>123</B>),
	57
	58	octal with a leading zero (e.g.
	59	<B>012</B>,
	60
	61	which has value 10),
	62	or hexadecimal with a leading
	63	<B>0x</B>
	64
65	(e.g.
66	<B>0x1f</B>,
67
68	which has value 31)
69	in either upper or lower case.
70	<P>
71
72	The
73	<I>srclen</I>
74
75	parameter of
76	<I>atoul</I>
77
78	specifies the length of the ASCII string pointed to by
79	<I>src</I>;
80
81	it is an error for there to be anything else
82	(e.g., a terminating NUL) within that length.
83	As a convenience for cases where an entire NUL-terminated string is
84	to be converted,
85	a
86	<I>srclen</I>
87
88	value of
89	<B>0</B>
90
91	is taken to mean
92	<B>strlen(src)</B>.
93
94	<P>
95
96	The
97	<I>base</I>
98
99	parameter of
100	<I>atoul</I>
101
102	can be
103	<B>8</B>,
104
105	<B>10</B>,
106
107	or
108	<B>16</B>,
109
110	in which case the number supplied is assumed to be of that form
111	(and in the case of
112	<B>16</B>,
113
114	to lack any
115	<B>0x</B>
116
117	prefix).
118	It can also be
119	<B>0</B>,
120
121	in which case the number is examined for a leading zero
122	or a leading
123	<B>0x</B>
124
125	to determine its base,
126	or
127	<B>13</B>
128
129	(halfway between 10 and 16),
130	which has the same effect as
131	<B>0</B>
132
133	except that a non-hexadecimal
134	number is considered decimal regardless of any leading zero.
135	<P>
136
137	The
138	<I>dstlen</I>
139
140	parameter of
141	<I>ultoa</I>
142
143	specifies the size of the
144	<I>dst</I>
145
146	parameter;
147	under no circumstances are more than
148	<I>dstlen</I>
149
150	bytes written to
151	<I>dst</I>.
152
153	A result which will not fit is truncated.
154	<I>Dstlen</I>
155
156	can be zero, in which case
157	<I>dst</I>
158
159	need not be valid and no result is written,
160	but the return value is unaffected;
161	in all other cases, the (possibly truncated) result is NUL-terminated.
162	<P>
163
164	The
165	<I>base</I>
166
167	parameter of
168	<I>ultoa</I>
169
170	must be
171	<B>8</B>,
172
173	<B>10</B>,
174
175	or
176	<B>16</B>.
177
178	<P>
179
180	<I>Atoul</I>
181
182	returns NULL for success and
183	a pointer to a string-literal error message for failure;
184	see DIAGNOSTICS.
185	<I>Ultoa</I>
186
187	returns the size of buffer which would
188	be needed to
189	accommodate the full conversion result, including terminating NUL;
190	it is the caller's responsibility to check this against the size of
191	the provided buffer to determine whether truncation has occurred.
192	<A NAME="lbAE"> </A>
193	<H2>SEE ALSO</H2>
194
195	<A HREF="atol.3.html">atol</A>(3), <A HREF="strtoul.3.html">strtoul</A>(3)
196	<A NAME="lbAF"> </A>
197	<H2>DIAGNOSTICS</H2>
198
199	Fatal errors in
200	<I>atoul</I>
201
202	are:
203	empty input;
204	unknown
205	<I>base</I>;
206
207	non-digit character found;
208	number too large for an
209	<B>unsigned long</B>.
210
211	<A NAME="lbAG"> </A>
212	<H2>HISTORY</H2>
213
214	Written for the FreeS/WAN project by Henry Spencer.
215	<A NAME="lbAH"> </A>
216	<H2>BUGS</H2>
217
218	There is no provision for reporting an invalid
219	<I>base</I>
220
221	parameter given to
222	<I>ultoa</I>.
223
224	<P>
225
226	The restriction of error reports to literal strings
227	(so that callers don't need to worry about freeing them or copying them)
228	does limit the precision of error reporting.
229	<P>
230
231	The error-reporting convention lends itself to slightly obscure code,
232	because many readers will not think of NULL as signifying success.
233	A good way to make it clearer is to write something like:
234	<P>
235
236	<DL COMPACT><DT><DD>
237	<PRE>
238	<B>const char *error;</B>
239
240	<B>error = atoul( /* ... */ );</B>
241	<B>if (error != NULL) {</B>
242	<B> /* something went wrong */</B>
243	</PRE>
244
245	</DL>
246
247	<P>
248
249	<HR>
250	<A NAME="index"> </A><H2>Index</H2>
251	<DL>
252	<DT><A HREF="#lbAB">NAME</A><DD>
253	<DT><A HREF="#lbAC">SYNOPSIS</A><DD>
254	<DT><A HREF="#lbAD">DESCRIPTION</A><DD>
255	<DT><A HREF="#lbAE">SEE ALSO</A><DD>
256	<DT><A HREF="#lbAF">DIAGNOSTICS</A><DD>
257	<DT><A HREF="#lbAG">HISTORY</A><DD>
258	<DT><A HREF="#lbAH">BUGS</A><DD>
259	</DL>
260	<HR>
261	This document was created by
262	<A HREF="http://localhost/cgi-bin/man/man2html">man2html</A>,
263	using the manual pages.<BR>
264	Time: 21:40:17 GMT, November 11, 2003
265	</BODY>
266	</HTML>