errata.html

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169-70	11.2	C99 *is* available in electronic form, for $18
		from www.ansi.org .

174	11.10	As written, the "complicated series of assignments"
		of course includes some declarations and initializations.
		[Thanks to James Stern]

175	11.10	"e.g., (const char) ** in this case" should be
		"e.g., (const char **) in this case"

		"when the pointers which" should either be
		"when the pointers" or "with pointers which"

180	11.19	"questions 20.20" should be "question 20.20"

182	11.25	"The function offers" should be
		"The memmove function offers".
		[Thanks and $1 to Gordon Burditt]

183-4	11.27	In C99, external identifiers are required
		to be unique in the first 32 characters;
		C90's extremely Spartan limitation to six
		characters has been relaxed.

186	11.29	You may also need to rework calls to realloc
		that use NULL or 0 as first or second arguments
		(see question 7.30).

186	11.29	You may also need to rework conditional compilation
		involving #elif.
		See also the Rationale's list of "Quiet Changes"
		(see question 11.2).
		[Thanks to James Stern]

189	11.33	A fourth class of behavior is locale-specific.
		[Thanks and $1 to James Stern]

198	12.11	A semicolon is missing after "int i = 0".

		The } just before the line "*p = '\0'" is
		indented one tab too few.

		Two instances of "*--p" have the minus signs merged
		so as to appear as one.

201	12.16	[case 2] The variable line is not declared;
		it should probably be a char [], suitably
		initialized, e.g.:

			char line[] = "1 2.3 4.5e6 789e10";

		[Thanks and $1 to James Stern]

205	12.19	There's an extraneous double quote in what
		should be "intervening whitespace:".

207-8	12.21	The technique of writing to a file may give the
		wrong answer if the disk fills up.
		[Thanks and $1 to Mark Brader]

		The "hope that a future revision of the ANSI/ISO
		C Standard will include" the snprintf function
		has been fulfilled: C99 does specify it.
		As a bonus, the C99 snprintf can be used to predict
		the size required for an arbitrary sprintf call,
		too -- it can be called with a null pointer
		instead of a destination buffer (and 0 as the
		size of that nonexistent buffer) and it returns
		the number of characters it would have written.

212	12.28	The answer is in the wrong font.

213	12.30	Updating (overwriting) a text file in-place is
		not fully portable; the C Standard leaves it
		implementation-defined whether a write to a
		text file truncates it at that point.
		[Thanks and $1 to Tanmoy Bhattacharya]

224	13.4	"upper- or lowercase" should probably be
		"upper or lower case".

225	13.6	Since the fragment calls printf, it must
		#include <stdio.h>.
		[Thanks and $1 to James Stern]

226	13.6	[last code fragment] A declaration and initialization

			char string[] = "this\thas\t\tmissing\tfield";

		similar to the one on p. 225 should appear.
		[Thanks and $1 to Doug Liu]

227	13.6	Also, since the input string is modified,
		it must be writable; see question 1.32.

234	13.14	"time_ts" should perhaps be "time_t's"

240	13.17	The code

			srand((unsigned int)time((time_t *)NULL));

		though popular and generally effective is, alas,
		not strictly conforming.  It's theoretically
		possible that time_t could be defined as a
		floating-point type under some implementation,
		and that the time_t values returned by time()
		could therefore exceed the range of an unsigned
		int in such a way that a well-defined cast to
		(unsigned int) is not possible.

242-3	13.20	The attributions listed for methods 2 and 3 are
		scrambled.  Method 2 is the one described in
		the 1958 Box and Muller paper (as well as by
		Abramowitz and Stegun, apparently).  Method 3
		is originally due to Marsaglia.

244	13.21	If you're not familiar with the notation [0, 1),
		it means that drand48() returns a number x
		such that 0 <= x and x < 1.

250	14.5	The suggested expression should read

			fabs(a - b) <= epsilon * fabs(a)

		It performs poorly if a == 0.0 (which is another
		argument in favor of "mak[ing] the threshold
		a function of b, or of both a and b").

253	14.8	Of course, you can always compute pi using
		4*atan(1.0) or acos(-1.0).
		[Thanks to James Stern and Clinton Sheppard]

253	14.9	C99 specifies isnan() and several other
		classification routines.

254-5	14.11	C99 supports complex as a standard type.

260-1	15.4	The first argument to vstrcat() could be const char *,
		as could the fmt argument to miniprintf().
		[Thanks to James Stern]

264	15.5	The fmt argument to error() could be const char *.

269-71	15.12	The fmt arguments to faterror(), verror(), and
		error() could all be const char *.

274	16.4	[point 2] The problem could be caused by a setbuf
		or setvbuf buffer local to any function.
		[Thanks and $1 to James Stern]

276	16.7	Variable "s" isn't declared.  It's pretty obvious
		what it should be, but to make it explicit, change
		the struct declaration to

			struct mystruct { ... } s;

		[Thanks to Peter Hryczanek]

287	18.1	The URL in the list of metrics tools is really
		"http://www.qucis.queensu.ca:1999/Software-Engineering/Cmetrics.html".

294	18.13	The conventional spelling is "NetBSD".
		[Thanks and $1 to Peter Seebach]

294	18.14	Extra space in site which should be "sunsite.unc.edu".

296	18.16	Extra space in address which should be
		"[e-mail]".

308	19.11	Note that a test using fopen() *is* approximate;
		failure does not necessarily indicate nonexistence.

310	19.14	Updating (overwriting) a text file in-place is
		not fully portable; the C Standard leaves it
		implementation-defined whether a write to a
		text file truncates it at that point.
		[Thanks and $1 to Tanmoy Bhattacharya]

314	19.23	In C99, the guarantee on the possible size of a
		single object has been raised to 64K.

315	19.25	Use of the `volatile' qualifier is often
		appropriate when performing memory-mapped I/O.
		[Thanks to Lee Crawford]

317	19.27	The return value of system() is not guaranteed
		to be the command's exit status.
		[Thanks and $1 to Peter Seebach]

318	19.30	If you forget to call pclose, it's probably at
		least as likely that you'll run out of file
		descriptors as processes.
		[Thanks and $1 to Jens Schweikhardt]

319	19.31	argv[0] may also be a null pointer.
		[Thanks and $1 to Tanmoy Bhattacharya]

324	19.42	"control characters, such as" should be
		"control characters such as"

339-40		The page break makes the code very hard to follow.

342-44	20.13	The tone of this question's answer can be read as
		suggesting that efficiency isn't important at all.
		That's not the case, of course -- efficiency can
		very important, and poorly-written programs can
		run abysmally inefficiently.

		The point is that there are good ways and bad
		ways of achieving an appropriate level of
		performance for a given program, and that (for
		example) picking a good algorithm tends to make a
		much bigger difference than does microoptimizing
		the coding details of a lesser algorithm.

346	20.17	Missing tab in line which should be

			#define CODE_NONE	0

350	20.21	The overbars are misaligned.

355	20.29	"and computes that number" should either be
		"computed" or "and is computed".

363		[aggregate] Unions are not aggregates.
		[Thanks and $1 to Kinichi Kitano]

368		[parameter] Extraneous semicolon at end of
		line which should be

			f(int i)

370-1		The glossary entry for "undefined" is misplaced.
		[Thanks and $1 to James Stern]

376		The two minus signs in the index entry for
		"-- operator" overlap and appear to be one.

379		The pairs of underscores in the index entry for
		"__FILE__ macro" overlap and might appear to be one.

382		The pairs of underscores in the index entry for
		"__LINE__ macro" overlap and might appear to be one.

back cover	"on the Usenet/Internet on the C FAQ" is muddled
		and should say something else.

		"com.lang.c" should be "comp.lang.c".

		The ftp address for source code should be
		ftp://ftp.aw.com/cseng/authors/summit/cfaq .

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