The document describes code for formatting output in C using printf formatting strings. It shows the internal functions and variables used to parse the format string and handle different conversion specifiers like %s, %f, etc. Key parts include the doformat() function which parses the format string and handles different cases, and code that writes output by calling fwrite().

9. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
[abcde]
[1.03]
[%]

10. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
[abcde]
[1.03]
[%]
[
abcde
]n[
1.03
]n[
%
]n
[ ... L151 fwrite(start, 1, fmt - start, stdout);
abcde ... L289 PF(start, p); => L87 (void)fputs(b, stdout);
]n[ ... L151 fwrite(start, 1, fmt - start, stdout);
1.03 ... L318 PF(start, p); => L87 (void)fputs(b, stdout);
]n[ ... L151 fwrite(start, 1, fmt - start, stdout);
%% ... L154 putchar('%');
]n ... L151 fwrite(start, 1, fmt - start, stdout);

11. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt;
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159 return (1);
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
166
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

12. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt;
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159 return (1);
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
166
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

13. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt;
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153
154
/* %% prints a % */
putchar('%');
[%s]n[%2.2f]n[%%]n
155 fmt += 2;
156 } else {
157
158
fmt = doformat(fmt, &rval);
if (fmt == NULL)
21
159 return (1);
160 end = 0;
161 }
162 start = fmt;
163 } else [%s]n
164 fmt++;
165 } [%2.2f]n
166
167 if (end == 1) { [%%]n
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval); 18
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

14. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt; static char **gargv;
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
“abcde”
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159 return (1);
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
166
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

15. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt;
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159 return (1);
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
166
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

16. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt;
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159
160
return (1);
end = 0;
start:char *
161
162
}
start = fmt;
[%s]n[%2.2f]n[%%]n
163 } else
164 fmt++;
165 } fmt:char *
166
167 if (end == 1) { [%s]n[%2.2f]n[%%]n
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

17. [
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) {
148 start = fmt;
149 while (fmt < format + len) { start:char *
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout); [%s]n[%2.2f]n[%%]n
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156
157
} else {
fmt = doformat(fmt, &rval);
fmt:char *
158 if (fmt == NULL) [%s]n[%2.2f]n[%%]n
159 return (1);
160 end = 0;
161 }
162 start = fmt; fmt - start == 1
163 } else
164 fmt++;
165 }
166 fwrite(
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL); “[%s]n[%2.2f]n[%%]n”,
169
170 }
return (1);
1, 1, stdout
171
172
fwrite(start, 1, fmt - start, stdout);
if (chopped || !*gargv)
);
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format; => “[“
176 end = 1;
177 }
178 /* NOTREACHED */

18. [
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) { fmt:char *
148 start = fmt;
149 while (fmt < format + len) { [%s]n[%2.2f]n[%%]n
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */ L157
154 putchar('%');
155 fmt += 2; fmt = doformat(
156 } else {
157 fmt = doformat(fmt, &rval); fmt, &rval
158 if (fmt == NULL)
159 return (1); );
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
166
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

19. [
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
185 static const char skip1[] = "#'-+ 0";
186 static const char skip2[] = "0123456789"; %hogehoge
191 fmt = start + 1;
192 /* skip to field width */
193 fmt += strspn(fmt, skip1);
194 if (*fmt == '*') {
195 if (getint(&fieldwidth))
196 return (NULL);
197 havewidth = 1;
198 ++fmt;
199 } else {
200 havewidth = 0;
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2);
204 }
205 if (*fmt == '.') {
206 /* precision present? */
207 ++fmt;
208 if (*fmt == '*') {
209 if (getint(&precision))
210 return (NULL);
211 haveprec = 1;
212 ++fmt;
213 } else {
214 haveprec = 0;
215
216 /* skip to conversion char */
217 fmt += strspn(fmt, skip2);
218 }
219 } else
220 haveprec = 0;

20. [
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
185 static const char skip1[] = "#'-+ 0";
186 static const char skip2[] = "0123456789";
191 fmt = start + 1;
192 /* skip to field width */ start:char *
193 fmt += strspn(fmt, skip1);
194 if (*fmt == '*') { [%s]n[%2.2f]n[%%]n
195 if (getint(&fieldwidth))
196 return (NULL);
197 havewidth = 1;
198 ++fmt; fmt:char *
199
200
} else {
havewidth = 0;
[%s]n[%2.2f]n[%%]n
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2);
204 }
205 if (*fmt == '.') {
206 /* precision present? */
207 ++fmt;
208 if (*fmt == '*') {
209 if (getint(&precision))
210 return (NULL);
211 haveprec = 1;
212 ++fmt;
213 } else {
214 haveprec = 0;
215
216 /* skip to conversion char */
217 fmt += strspn(fmt, skip2);
218 }
219 } else
220 haveprec = 0;

21. [
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
convch:char == ‘s’
247 convch = *fmt;
248 nextch = *++fmt; nextch:char == ‘]’
249 *fmt = '0';
250 switch (convch) {
251 case 'b': { fmt:char *
252 size_t len;
253 char *p; [%s0n[%2.2f]n[%%]n
254 int getout;
255
285 case 's': {
start:char *
286
287
const char *p; [%s0n[%2.2f]n[%%]n
288 p = getstr();
289 PF(start, p);
290 break;
291 }

22. [
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
247 convch = *fmt;
248 nextch = *++fmt;
249 *fmt = '0';
250 switch (convch) {
251 case 'b': {
252 size_t len;
253 char *p;
254 int getout;
255
285 case 's': {
286 const char *p;
287
288 p = getstr();
289 PF(start, p);
290 break;
291 } 442 static const char *
443 getstr(void)
444 {
445 if (!*gargv)
446 return ("");
447 return (*gargv++);
448 }

23. [abcde
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
247 convch = *fmt;
248 nextch = *++fmt;
249 *fmt = '0';
250
251
switch (convch) {
case 'b': {
[%s0n[%2.2f]n[%%]n
252 size_t len;
253 char *p;
254 int getout;
255
285 case 's': {
286 const char *p;
287 “abcde”
288 p = getstr();
289 PF(start, p);
290 break; 75 #define PF(f, func) do {
291 } 76 char *b = NULL;
77 if (havewidth)
78 if (haveprec)
79 (void)asprintf(&b, f, fieldwidth, precision, func);
80 else
81 (void)asprintf(&b, f, fieldwidth, func);
82 else if (haveprec)
83 (void)asprintf(&b, f, precision, func);
84 else
85 (void)asprintf(&b, f, func);
86 if (b) {
87
88
(void)fputs(b, stdout);
free(b); [abcde
89 }
90 } while (0)

24. [abcde
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
nextch:char == ‘]’
285 case 's': {
286 const char *p;
287
288 p = getstr(); fmt:char *
289 PF(start, p);
290 break; [%s0n[%2.2f]n[%%]n
291 }
! ! !
330 *fmt = nextch;
331 return (fmt); [%s]n[%2.2f]n[%%]n
332 }
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159 return (1); [%s]n[%2.2f]n[%%]n
160 end = 0;
161 }
162 start = fmt;
! ! ! !
fmt:char *
[%s]n[%2.2f]n[%%]n
start:char *
[%s]n[%2.2f]n[%%]n

25. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */ fmt:char *
154
155
putchar('%');
fmt += 2;
[%s]n[%2.2f]n[%%]n
156 } else {
157 fmt = doformat(fmt, &rval);
158
159
if (fmt == NULL)
return (1);
start:char *
160 end = 0; [%s]n[%2.2f]n[%%]n
161 }
162 start = fmt;
163 } else
164 fmt++; fwrite(
165 }
start, // ]n[%2...
1, // 1
fmt - start, // 3
stdout
);
=> “]n[“

26. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
143 fmt = format = *argv;
144 chopped = escape(fmt, 1, &len); /* backslash interpretation */
145 rval = end = 0;
146 gargv = ++argv;
147 for (;;) { fmt:char *
148 start = fmt;
149 while (fmt < format + len) { [%s]n[%2.2f]n[%%]n
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */ L157
154 putchar('%');
155 fmt += 2; fmt = doformat(
156 } else {
157 fmt = doformat(fmt, &rval); fmt, &rval
158 if (fmt == NULL)
159 return (1); );
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
166
167 if (end == 1) {
168 warnx1("missing format character", NULL, NULL);
169 return (1);
170 }
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
178 /* NOTREACHED */

27. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval) start:char *
184 {
185 static const char skip1[] = "#'-+ 0"; [%s]n[%2.2f]n[%%]n
186 static const char skip2[] = "0123456789";
191 fmt = start + 1;
192 /* skip to field width */ fmt:char *
193
194
fmt += strspn(fmt, skip1);
if (*fmt == '*') {
[%s]n[%2.2f]n[%%]n
195 if (getint(&fieldwidth))
196 return (NULL);
197 havewidth = 1;
198 ++fmt;
199 } else {
200 havewidth = 0;
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2);
204 }
205 if (*fmt == '.') {
206 /* precision present? */
207 ++fmt;
208 if (*fmt == '*') {
209 if (getint(&precision))
210 return (NULL);
211 haveprec = 1;
212 ++fmt;
213 } else {
214 haveprec = 0;
215
216 /* skip to conversion char */
217 fmt += strspn(fmt, skip2);
218 }
219 } else
220 haveprec = 0;

28. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
185 static const char skip1[] = "#'-+ 0"; fmt:char *
186 static const char skip2[] = "0123456789";
[%s]n[%2.2f]n[%%]n
191 fmt = start + 1;
192 /* skip to field width */
193 fmt += strspn(fmt, skip1);
194 if (*fmt == '*') {
195 if (getint(&fieldwidth)) skip1 [#’-+ 0]
196 return (NULL);
197 havewidth = 1;
198 ++fmt;
199 } else {
200 havewidth = 0;
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2);
204 }
205 if (*fmt == '.') {
206 /* precision present? */
207 ++fmt;
208 if (*fmt == '*') {
209 if (getint(&precision))
210 return (NULL);
211 haveprec = 1;
212 ++fmt;
213 } else {
214 haveprec = 0;
215
216 /* skip to conversion char */
217 fmt += strspn(fmt, skip2);
218 }
219 } else
220 haveprec = 0;

29. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
185 static const char skip1[] = "#'-+ 0";
186 static const char skip2[] = "0123456789";
191 fmt = start + 1; fmt:char*
192 /* skip to field width */
193 fmt += strspn(fmt, skip1); [%s]n[%2.2f]n[%%]n
194 if (*fmt == '*') {
195 if (getint(&fieldwidth))
196 return (NULL);
197 havewidth = 1;
198 ++fmt;
199 } else {
200 havewidth = 0;
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2);
204 }
205 if (*fmt == '.') {
206 /* precision present? */
207 ++fmt;
208 if (*fmt == '*') { fmt:char*
209 if (getint(&precision))
210 return (NULL); [%s]n[%2.2f]n[%%]n
211 haveprec = 1;
212 ++fmt;
213 } else {
214 haveprec = 0;
215
216 /* skip to conversion char */
217 fmt += strspn(fmt, skip2);
218 }
219 } else
220 haveprec = 0;

30. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
185 static const char skip1[] = "#'-+ 0";
186 static const char skip2[] = "0123456789";
191 fmt = start + 1;
192 /* skip to field width */
193 fmt += strspn(fmt, skip1);
194 if (*fmt == '*') {
195 if (getint(&fieldwidth))
196 return (NULL);
197
198
havewidth = 1;
++fmt;
fmt:char*
199
200
} else {
havewidth = 0;
[%s]n[%2.2f]n[%%]n
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2);
204 }
205 if (*fmt == '.') {
206 /* precision present? */
207 ++fmt;
208
209
if (*fmt == '*') {
if (getint(&precision))
fmt:char*
210 return (NULL); [%s]n[%2.2f]n[%%]n
211 haveprec = 1;
212 ++fmt;
213 } else {
214 haveprec = 0;
215
216
217
/* skip to conversion char */
fmt += strspn(fmt, skip2);
fmt:start*
218 } [%s]n[%2.2f]n[%%]n
219 } else
220 haveprec = 0;

31. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
185 static const char skip1[] = "#'-+ 0";
186 static const char skip2[] = "0123456789";
191 fmt = start + 1;
192 /* skip to field width */
193 fmt += strspn(fmt, skip1);
194 if (*fmt == '*') {
195 if (getint(&fieldwidth))
196 return (NULL);
197 havewidth = 1;
198 ++fmt;
199 } else {
200 havewidth = 0;
201
202 /* skip to possible '.', get following precision */
203 fmt += strspn(fmt, skip2); fmt:char*
204 }
205 if (*fmt == '.') { [%s]n[%2.2f]n[%%]n
206 /* precision present? */
207 ++fmt;
208 if (*fmt == '*') {
209 if (getint(&precision))
210 return (NULL);
211 haveprec = 1;
212 ++fmt;
213
214
} else {
haveprec = 0;
fmt:char*
215
216 /* skip to conversion char */
[%s]n[%2.2f]n[%%]n
217 fmt += strspn(fmt, skip2);
218 }
219 } else
220 haveprec = 0;

32. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
convch:char == ‘f’
247 convch = *fmt;
248 nextch = *++fmt; nextch:char == ‘]’
249 *fmt = '0';
250 switch (convch) {
251 case 'b': { fmt:char *
252 size_t len;
253 char *p; [%s]n[%2.2f0n[%%]n
254 int getout;
255
285 case 's': {
start:char *
286
287
const char *p; [%s0n[%2.2f0n[%%]n
288 p = getstr();
289 PF(start, p);
290 break;
291 }

33. [abcde]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
247 convch = *fmt;
248 nextch = *++fmt;
249 *fmt = '0';
250 switch (convch) {
251 case 'b': {
252 size_t len;
253 char *p;
254 int getout;
255
309 case 'e': case 'E':
310 case 'f': case 'F':
311 case 'g': case 'G':
312 case 'a': case 'A': {
313 long double p;
314
315 if (getfloating(&p, mod_ldbl))
316 *rval = 1;
317 if (mod_ldbl)
318 PF(start, p);
319 else
320 PF(start, (double)p);
321 break; 507 static int
322 } 508 getfloating(long double *dp, int
mod_ldbl)
509 {
510 char *ep;
511 int rval;
512
526 *dp = strtod(*gargv, &ep);

34. [abcde]
[1.03
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
247 convch = *fmt;
248 nextch = *++fmt;
249 *fmt = '0';
[%s]n[%2.2f0n[%%]n
250 switch (convch) {
251 case 'b': {
252 size_t len;
253 char *p;
254 int getout;
255
309
310
case
case
'e': case 'E':
'f': case 'F':
1.034
311 case 'g': case 'G':
312 case 'a': case 'A': {
313 long double p; 75 #define PF(f, func) do {
314 76 char *b = NULL;
315 if (getfloating(&p, mod_ldbl)) 77 if (havewidth)
316 *rval = 1; 78 if (haveprec)
317 if (mod_ldbl) 79 (void)asprintf(&b, f, fieldwidth, precision, func);
318 PF(start, p); 80 else
319 else 81 (void)asprintf(&b, f, fieldwidth, func);
320 PF(start, (double)p); 82 else if (haveprec)
321 break; 83 (void)asprintf(&b, f, precision, func);
322 } 84 else
85 (void)asprintf(&b, f, func);
86 if (b) {
87 (void)fputs(b, stdout);
88 free(b);
89 }
90 } while (0)

35. [abcde]
[1.03
$ printf "[%s]n[%2.2f]n[%%]n" abcdf 1.034
182 static char *
183 doformat(char *start, int *rval)
184 {
nextch:char == ‘]’
309 case 'e': case 'E':
310 case 'f': case 'F':
311 case 'g': case 'G':
312 case 'a': case 'A': { fmt:char *
313 long double p;
314 [%s]n[%2.2f0n[%%]n
315 if (getfloating(&p, mod_ldbl))
316 *rval = 1; ! ! !
317 if (mod_ldbl)
318 PF(start, p); [%s]n[%2.2f]n[%%]n
319 else
320 PF(start, (double)p);
321 break;
322 }
330 *fmt = nextch;
331 return (fmt); [%s]n[%2.2f]n[%%]n
332 }
157
158
fmt = doformat(fmt, &rval);
if (fmt == NULL)
! ! ! !
159 return (1);
160 end = 0;
161 }
162 start = fmt; fmt:char *
[%s]n[%2.2f]n[%%]n
start:char *
[%s]n[%2.2f]n[%%]n

36. [abcde]
[1.03]
[
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */ fmt:char *
154
155
putchar('%');
fmt += 2;
[%s]n[%2.2f]n[%%]n
156 } else {
157 fmt = doformat(fmt, &rval);
158
159
if (fmt == NULL)
return (1);
fm
160 end = 0; [%s]n[%2.2f]n[%%]n
161 }
162 start = fmt;
163 } else
164 fmt++; fwrite(
165 }
start, // ]n[%%...
1, // 1
fmt - start, // 3
stdout
);
=> “]n[“

37. [abcde]
[1.03]
[%
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval); fmt:char *
158 if (fmt == NULL)
159 return (1); [%s]n[%2.2f]n[%%]n
160 end = 0;
161 }
162
163
start = fmt;
} else
start:char *
164
165 }
fmt++;
[%s]n[%2.2f]n[%%]n

38. [abcde]
[1.03]
[%]
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval); fmt:char *
158 if (fmt == NULL)
159 return (1); [%s]n[%2.2f]n[%%]n?
160 end = 0;
161 }
162
163
start = fmt;
} else
start:char *
164
165 }
fmt++;
[%s]n[%2.2f]n[%%]n
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);

39. [abcde]
[1.03]
[%]
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
149 while (fmt < format + len) {
150 if (fmt[0] == '%') {
151 fwrite(start, 1, fmt - start, stdout);
152 if (fmt[1] == '%') {
153 /* %% prints a % */
154 putchar('%');
155 fmt += 2;
156 } else {
157 fmt = doformat(fmt, &rval);
158 if (fmt == NULL)
159 return (1);
160 end = 0;
161 }
162 start = fmt;
163 } else
164 fmt++;
165 }
0
171 fwrite(start, 1, fmt - start, stdout);
172 if (chopped || !*gargv)
173 return (rval);

40. $ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034
147 for (;;) {
148 start = fmt;
174 /* Restart at the beginning of the format string. */
175 fmt = format;
176 end = 1;
177 }
$ printf "[%s]n[%2.2f]n[%%]n" abcde 1.034 fghij 23.4
[abcde]
1.03
[fghij]
23.40

41. 177 }
178 /* NOTREACHED */
179 }