1 '\" te
2 .\" Copyright 2014 Garrett D'Amore <garrett@damore.org>
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35 .TH PRINTF 1 "May 11, 2014"
36 .SH NAME
37 printf \- write formatted output
38 .SH SYNOPSIS
39 .SS "/usr/bin/printf"
40 .LP
41 .nf
42 \fBprintf\fR \fIformat\fR [\fIargument\fR]...
43 .fi
44
45 .SS "ksh93"
46 .LP
47 .nf
48 \fBprintf\fR \fIformat\fR [\fIstring\fR...]
49 .fi
50
51 .SH DESCRIPTION
52 .SS "/usr/bin/printf"
53 .sp
54 .LP
55 The \fBprintf\fR utility writes each string operand to standard output using
56 \fIformat\fR to control the output format.
57 .SH OPERANDS
58 .SS "/usr/bin/printf"
59 .sp
60 .LP
61 The following operands are supported by \fB/usr/bin/printf\fR:
62 .sp
63 .ne 2
64 .na
65 \fB\fIformat\fR\fR
66 .ad
67 .RS 12n
68 A string describing the format to use to write the remaining operands. The
69 \fIformat\fR operand is used as the \fIformat\fR string described on the
70 \fBformats\fR(5) manual page, with the following exceptions:
71 .RS +4
72 .TP
73 .ie t \(bu
74 .el o
75 A \fBSPACE\fR character in the format string, in any context other than a flag
76 of a conversion specification, is treated as an ordinary character that is
77 copied to the output.
78 .RE
79 .RS +4
80 .TP
81 .ie t \(bu
82 .el o
83 A character in the format string is treated as a character, not as a
84 \fBSPACE\fR character.
85 .RE
86 .RS +4
87 .TP
88 .ie t \(bu
89 .el o
90 In addition to the escape sequences described on the \fBformats\fR(5) manual
91 page (\fB\e\e\fR, \fB\ea\fR, \fB\eb\fR, \fB\ef\fR, \fB\en\fR, \fB\er\fR,
92 \fB\et\fR, \fB\ev\fR), \fB\e\fR\fIddd\fR, where \fIddd\fR is a one-, two- or
93 three-digit octal number, is written as a byte with the numeric value specified
94 by the octal number.
95 .RE
96 .RS +4
97 .TP
98 .ie t \(bu
99 .el o
100 The program does not precede or follow output from the \fBd\fR or \fBu\fR
101 conversion specifications with blank characters not specified by the
102 \fIformat\fR operand.
103 .RE
104 .RS +4
105 .TP
106 .ie t \(bu
107 .el o
108 The program does not precede output from the \fBo\fR conversion specification
109 with zeros not specified by the \fIformat\fR operand.
110 .RE
111 .RS +4
112 .TP
113 .ie t \(bu
114 .el o
115 The argument used for the conversion character (or width or precision
116 parameters, see below) may be taken from the \fIn\fRnth argument instead
117 of the next unused argument, by specifying \fIn\fR\fB$\fR immediately following
118 the \fB%\fR character, or the \fB*\fR character (for width or precision
119 arguments).
120 If \fIn\fR\fB$\fR appears in any conversions in the format string,
121 then it must be used for all conversions, including any variable width or
122 precision specifiers.
123 .RE
124 .RS +4
125 .TP
126 .ie t \(bu
127 .el o
128 The special character \fB*\fR may be used instead of a string of decimal digits
129 to indicate a minimum field width or a precision. In this case the next
130 available argument is used (or the \fIn\fRth if the form \fIn\fR\fB$\fR is
131 used), treating its value as a decimal string.
132 .RE
133 .RS +4
134 .TP
135 .ie t \(bu
136 .el o
137 An additional conversion character, \fBb\fR, is supported as follows. The
138 argument is taken to be a string that can contain backslash-escape sequences.
139 The following backslash-escape sequences are supported:
140 .RS +4
141 .TP
142 .ie t \(bu
143 .el o
144 the escape sequences listed on the \fBformats\fR(5) manual page (\fB\e\e\fR,
145 \fB\ea\fR, \fB\eb\fR, \fB\ef\fR, \fB\en\fR, \fB\er\fR, \fB\et\fR, \fB\ev\fR),
146 which are converted to the characters they represent
147 .RE
148 .RS +4
149 .TP
150 .ie t \(bu
151 .el o
152 \fB\e0\fR\fIddd\fR, where \fIddd\fR is a zero-, one-, two- or three-digit octal
153 number that is converted to a byte with the numeric value specified by the
154 octal number
155 .RE
156 .RS +4
157 .TP
158 .ie t \(bu
159 .el o
160 \fB\ec\fR, which is written and causes \fBprintf\fR to ignore any remaining
161 characters in the string operand containing it, any remaining string operands
162 and any additional characters in the \fIformat\fR operand.
163 .RE
164 .RE
165 The interpretation of a backslash followed by any other sequence of characters
166 is unspecified.
167 .sp
168 Bytes from the converted string are written until the end of the string or the
169 number of bytes indicated by the precision specification is reached. If the
170 precision is omitted, it is taken to be infinite, so all bytes up to the end of
171 the converted string are written. For each specification that consumes an
172 argument, the next argument operand is evaluated and converted to the
173 appropriate type for the conversion as specified below. The \fIformat\fR
174 operand is reused as often as necessary to satisfy the argument operands. Any
175 extra \fBc\fR or \fBs\fR conversion specifications are evaluated as if a null
176 string argument were supplied; other extra conversion specifications are
177 evaluated as if a zero argument were supplied.
178 .sp
179 When there are more argument operands than format specifiers, and the
180 format includes \fIn\fR\fB$\fR position indicators, then the format is
181 reprocessed from the beginning as above, but with the argument list starting
182 from the next argument after the highest \fIn\fRth argument previously
183 encountered.
184 .sp
185 If the \fIformat\fR operand
186 contains no conversion specifications and \fIargument\fR operands are present,
187 the results are unspecified. If a character sequence in the \fIformat\fR
188 operand begins with a \fB%\fR character, but does not form a valid conversion
189 specification, the behavior is unspecified.
190 .RE
191
192 .sp
193 .ne 2
194 .na
195 \fB\fIargument\fR\fR
196 .ad
197 .RS 12n
198 The strings to be written to standard output, under the control of
199 \fBformat\fR. The \fIargument\fR operands are treated as strings if the
200 corresponding conversion character is \fBb\fR, \fBc\fR or \fBs\fR. Otherwise,
201 it is evaluated as a C constant, as described by the ISO C standard, with the
202 following extensions:
203 .RS +4
204 .TP
205 .ie t \(bu
206 .el o
207 A leading plus or minus sign is allowed.
208 .RE
209 .RS +4
210 .TP
211 .ie t \(bu
212 .el o
213 If the leading character is a single- or double-quote, the value is the numeric
214 value in the underlying codeset of the character following the single- or
215 double-quote.
216 .RE
217 If an argument operand cannot be completely converted into an internal value
218 appropriate to the corresponding conversion specification, a diagnostic message
219 is written to standard error and the utility does not exit with a zero exit
220 status, but continues processing any remaining operands and writes the value
221 accumulated at the time the error was detected to standard output.
222 .RE
223
224 .SS "ksh93"
225 .sp
226 .LP
227 The \fIformat\fR operands support the full range of ANSI C/C99/XPG6 formatting
228 specifiers as well as additional specifiers:
229 .sp
230 .ne 2
231 .na
232 \fB\fB%b\fR\fR
233 .ad
234 .RS 6n
235 Each character in the string operand is processed specially, as follows:
236 .sp
237 .ne 2
238 .na
239 \fB\fB\ea\fR\fR
240 .ad
241 .RS 8n
242 Alert character.
243 .RE
244
245 .sp
246 .ne 2
247 .na
248 \fB\fB\eb\fR\fR
249 .ad
250 .RS 8n
251 Backspace character.
252 .RE
253
254 .sp
255 .ne 2
256 .na
257 \fB\fB\ec\fR\fR
258 .ad
259 .RS 8n
260 Terminate output without appending NEWLINE. The remaining string operands are
261 ignored.
262 .RE
263
264 .sp
265 .ne 2
266 .na
267 \fB\fB\eE\fR\fR
268 .ad
269 .RS 8n
270 Escape character (\fBASCII\fR octal \fB033\fR).
271 .RE
272
273 .sp
274 .ne 2
275 .na
276 \fB\fB\ef\fR\fR
277 .ad
278 .RS 8n
279 FORM FEED character.
280 .RE
281
282 .sp
283 .ne 2
284 .na
285 \fB\fB\en\fR\fR
286 .ad
287 .RS 8n
288 NEWLINE character.
289 .RE
290
291 .sp
292 .ne 2
293 .na
294 \fB\fB\et\fR\fR
295 .ad
296 .RS 8n
297 TAB character.
298 .RE
299
300 .sp
301 .ne 2
302 .na
303 \fB\fB\ev\fR\fR
304 .ad
305 .RS 8n
306 Vertical tab character.
307 .RE
308
309 .sp
310 .ne 2
311 .na
312 \fB\fB\e\e\fR\fR
313 .ad
314 .RS 8n
315 Backslash character.
316 .RE
317
318 .sp
319 .ne 2
320 .na
321 \fB\fB\e0\fR\fIx\fR\fR
322 .ad
323 .RS 8n
324 The 8-bit character whose \fBASCII\fR code is the \fB1\fR-, \fB2\fR-, or
325 \fB3\fR-digit octal number \fIx\fR.
326 .RE
327
328 .RE
329
330 .sp
331 .ne 2
332 .na
333 \fB\fB%B\fR\fR
334 .ad
335 .RS 6n
336 Treat the argument as a variable name and output the value without converting
337 it to a string. This is most useful for variables of type \fB-b\fR.
338 .RE
339
340 .sp
341 .ne 2
342 .na
343 \fB\fB%H\fR\fR
344 .ad
345 .RS 6n
346 Output string with characters \fB<\fR, \fB&\fR, \fB>\fR, \fB"\fR, and
347 non-printable characters, properly escaped for use in HTML and XML documents.
348 .RE
349
350 .sp
351 .ne 2
352 .na
353 \fB\fB%P\fR\fR
354 .ad
355 .RS 6n
356 Treat \fIstring\fR as an extended regular expression and convert it to a shell
357 pattern.
358 .RE
359
360 .sp
361 .ne 2
362 .na
363 \fB\fB%q\fR\fR
364 .ad
365 .RS 6n
366 Output \fIstring\fR quoted in a manner that it can be read in by the shell to
367 get back the same string. However, empty strings resulting from missing string
368 operands are not quoted.
369 .RE
370
371 .sp
372 .ne 2
373 .na
374 \fB\fB%R\fR\fR
375 .ad
376 .RS 6n
377 Treat \fIstring\fR as an shell pattern expression and convert it to an extended
378 regular expression.
379 .RE
380
381 .sp
382 .ne 2
383 .na
384 \fB\fB%T\fR\fR
385 .ad
386 .RS 6n
387 Treat \fIstring\fR as a date/time string and format it. The \fBT\fR can be
388 preceded by (\fIdformat\fR), where \fIdformat\fR is a date format as defined by
389 the \fBdate\fR(1) command.
390 .RE
391
392 .sp
393 .ne 2
394 .na
395 \fB\fB%Z\fR\fR
396 .ad
397 .RS 6n
398 Output a byte whose value is \fB0\fR.
399 .RE
400
401 .sp
402 .LP
403 When performing conversions of \fIstring\fR to satisfy a numeric format
404 specifier, if the first character of \fIstring\fR is \fB"or'\fR, the value is
405 the numeric value in the underlying code set of the character following the
406 \fB"or'\fR. Otherwise, \fIstring\fR is treated like a shell arithmetic
407 expression and evaluated.
408 .sp
409 .LP
410 If a \fIstring\fR operand cannot be completely converted into a value
411 appropriate for that format specifier, an error occurs, but remaining
412 \fIstring\fR operands continue to be processed.
413 .sp
414 .LP
415 In addition to the format specifier extensions, the following extensions of
416 ANSI C/C99/XPG6 are permitted in format specifiers:
417 .RS +4
418 .TP
419 .ie t \(bu
420 .el o
421 The escape sequences \fB\eE\fR and \fB\ee\fR expand to the escape character
422 which is octal 033 in ASCII.
423 .RE
424 .RS +4
425 .TP
426 .ie t \(bu
427 .el o
428 The escape sequence \fB\ecx\fR expands to CTRL-x.
429 .RE
430 .RS +4
431 .TP
432 .ie t \(bu
433 .el o
434 The escape sequence \fB\eC[.\fR\fIname\fR\fB\&.]\fR expands to the collating
435 element \fIname\fR.
436 .RE
437 .RS +4
438 .TP
439 .ie t \(bu
440 .el o
441 The escape sequence \fB\ex{hex}\fR expands to the character corresponding to
442 the hexadecimal value \fBhex\fR.
443 .RE
444 .RS +4
445 .TP
446 .ie t \(bu
447 .el o
448 The format modifier flag = can be used to center a field to a specified width.
449 When the output is a terminal, the character width is used rather than the
450 number of bytes.
451 .RE
452 .RS +4
453 .TP
454 .ie t \(bu
455 .el o
456 Each of the integral format specifiers can have a third modifier after width
457 and precision that specifies the base of the conversion from 2 to 64. In this
458 case, the \fB#\fR modifier causes \fIbase\fR\fB#\fR to be prepended to the
459 value.
460 .RE
461 .RS +4
462 .TP
463 .ie t \(bu
464 .el o
465 The \fB#\fR modifier can be used with the \fBd\fR specifier when no base is
466 specified to cause the output to be written in units of 1000 with a suffix of
467 one of \fBk M G T P E\fR.
468 .RE
469 .RS +4
470 .TP
471 .ie t \(bu
472 .el o
473 The \fB#\fR modifier can be used with the \fBi\fR specifier to cause the output
474 to be written in units of \fB1024\fR with a suffix of one of \fBKi Mi Gi Ti Pi
475 Ei\fR.
476 .RE
477 .sp
478 .LP
479 If there are more \fIstring\fR operands than format specifiers, the format
480 string is reprocessed from the beginning. If there are fewer \fIstring\fR
481 operands than format specifiers, then \fIstring\fR specifiers are treated as if
482 empty strings were supplied, numeric conversions are treated as if \fB0\fR was
483 supplied, and time conversions are treated as if \fBnow\fR was supplied.
484 .sp
485 .LP
486 When there are more argument operands than format specifiers, and the
487 format includes \fIn\fR\fB$\fR position indicators, then the format is
488 reprocessed from the beginning as above, but with the argument list starting
489 from the next argument after the highest \fIn\fRth argument previously
490 encountered.
491 .sp
492 .LP
493 \fB/usr/bin/printf\fR is equivalent to \fBksh93\fR's \fBprintf\fR built-in and
494 \fBprint -f\fR, which allows additional options to be specified.
495 .SH USAGE
496 .SS "/usr/bin/printf"
497 .sp
498 .LP
499 The \fBprintf\fR utility, like the \fBprintf\fR(3C) function on which it is
500 based, makes no special provision for dealing with multi-byte characters when
501 using the \fB%c\fR conversion specification. Applications should be extremely
502 cautious using either of these features when there are multi-byte characters in
503 the character set.
504 .sp
505 .LP
506 The \fB%b\fR conversion specification is not part of the ISO C standard; it has
507 been added here as a portable way to process backslash escapes expanded in
508 string operands as provided by the \fBecho\fR utility. See also the USAGE
509 section of the \fBecho\fR(1) manual page for ways to use \fBprintf\fR as a
510 replacement for all of the traditional versions of the \fBecho\fR utility.
511 .sp
512 .LP
513 If an argument cannot be parsed correctly for the corresponding conversion
514 specification, the \fBprintf\fR utility reports an error. Thus, overflow and
515 extraneous characters at the end of an argument being used for a numeric
516 conversion are to be reported as errors.
517 .sp
518 .LP
519 It is not considered an error if an argument operand is not completely used for
520 a \fBc\fR or \fBs\fR conversion or if a string operand's first or second
521 character is used to get the numeric value of a character.
522 .SH EXAMPLES
523 .SS "/usr/bin/printf"
524 .LP
525 \fBExample 1 \fRPrinting a Series of Prompts
526 .sp
527 .LP
528 The following example alerts the user, then prints and reads a series of
529 prompts:
530
531 .sp
532 .in +2
533 .nf
534 example% \fBprintf "\eaPlease fill in the following: \enName: "
535 read name
536 printf "Phone number: "
537 read phone\fR
538 .fi
539 .in -2
540 .sp
541
542 .LP
543 \fBExample 2 \fRPrinting a Table of Calculations
544 .sp
545 .LP
546 The following example prints a table of calculations. It reads out a list of
547 right and wrong answers from a file, calculates the percentage correctly, and
548 prints them out. The numbers are right-justified and separated by a single tab
549 character. The percentage is written to one decimal place of accuracy:
550
551 .sp
552 .in +2
553 .nf
554 example% \fBwhile read right wrong ; do
555 percent=$(echo "scale=1;($right*100)/($right+$wrong)" | bc)
556 printf "%2d right\et%2d wrong\et(%s%%)\en" \e
557 $right $wrong $percent
558 done < database_file\fR
559 .fi
560 .in -2
561 .sp
562
563 .LP
564 \fBExample 3 \fRPrinting number strings
565 .sp
566 .LP
567 The command:
568
569 .sp
570 .in +2
571 .nf
572 example% \fBprintf "%5d%4d\en" 1 21 321 4321 54321\fR
573 .fi
574 .in -2
575 .sp
576
577 .sp
578 .LP
579 produces:
580
581 .sp
582 .in +2
583 .nf
584 1 21
585 3214321
586 54321 0
587 .fi
588 .in -2
589 .sp
590
591 .sp
592 .LP
593 The \fIformat\fR operand is used three times to print all of the given strings
594 and that a \fB0\fR was supplied by \fBprintf\fR to satisfy the last \fB%4d\fR
595 conversion specification.
596
597 .LP
598 \fBExample 4 \fRTabulating Conversion Errors
599 .sp
600 .LP
601 The following example tabulates conversion errors.
602
603 .sp
604 .LP
605 The \fBprintf\fR utility tells the user when conversion errors are detected
606 while producing numeric output. These results would be expected on an
607 implementation with 32-bit twos-complement integers when \fB%d\fR is specified
608 as the \fIformat\fR operand:
609
610 .sp
611
612 .sp
613 .TS
614 box;
615 c c c
616 l l l .
617 Arguments Standard Diagnostic
618 5a 5 printf: 5a not completely converted
619 9999999999 2147483647 printf: 9999999999: Results too large
620 -9999999999 -2147483648 printf: -9999999999: Results too large
621 ABC 0 printf: ABC expected numeric value
622 .TE
623
624 .sp
625 .LP
626 The value shown on standard output is what would be expected as the return
627 value from the function \fBstrtol\fR(3C). A similar correspondence exists
628 between \fB%u\fR and \fBstrtoul\fR(3C), and \fB%e\fR, \fB%f\fR and \fB%g\fR and
629 \fBstrtod\fR(3C).
630
631 .LP
632 \fBExample 5 \fRPrinting Output for a Specific Locale
633 .sp
634 .LP
635 The following example prints output for a specific locale. In a locale using
636 the ISO/IEC 646:1991 standard as the underlying codeset, the command:
637
638 .sp
639 .in +2
640 .nf
641 example% \fBprintf "%d\en" 3 +3 -3 \e'3 \e"+3 "'-3"\fR
642 .fi
643 .in -2
644 .sp
645
646 .sp
647 .LP
648 produces:
649
650 .sp
651
652 .sp
653 .TS
654 box;
655 l l
656 l l .
657 \fB3\fR Numeric value of constant 3
658 \fB3\fR Numeric value of constant 3
659 \fB\(mi3\fR Numeric value of constant \(mi3
660 \fB51\fR T{
661 Numeric value of the character `3' in the ISO/IEC 646:1991 standard codeset
662 T}
663 \fB43\fR T{
664 Numeric value of the character `+' in the ISO/IEC 646:1991 standard codeset
665 T}
666 \fB45\fR T{
667 Numeric value of the character `\(mi' in the SO/IEC 646:1991 standard codeset
668 T}
669 .TE
670
671 .sp
672 .LP
673 In a locale with multi-byte characters, the value of a character is intended to
674 be the value of the equivalent of the \fBwchar_t\fR representation of the
675 character.
676
677 .sp
678 .LP
679 If an argument operand cannot be completely converted into an internal value
680 appropriate to the corresponding conversion specification, a diagnostic message
681 is written to standard error and the utility does exit with a zero exit status,
682 but continues processing any remaining operands and writes the value
683 accumulated at the time the error was detected to standard output.
684
685 .LP
686 \fBExample 6 \fRAlternative floating point representation 1
687 .sp
688 .LP
689 The \fBprintf\fR utility supports an alternative floating point representation
690 (see \fBprintf\fR(3C) entry for the "\fB%a\fR"/"\fB%A\fR"), which allows the
691 output of floating-point values in a format that avoids the usual base16 to
692 base10 rounding errors.
693
694 .sp
695 .in +2
696 .nf
697 example% printf "%a\en" 2 3.1 NaN
698 .fi
699 .in -2
700 .sp
701
702 .sp
703 .LP
704 produces:
705
706 .sp
707 .in +2
708 .nf
709 0x1.0000000000000000000000000000p+01
710 0x1.8ccccccccccccccccccccccccccdp+01
711 nan
712 .fi
713 .in -2
714 .sp
715
716 .LP
717 \fBExample 7 \fRAlternative floating point representation 2
718 .sp
719 .LP
720 The following example shows two different representations of the same
721 floating-point value.
722
723 .sp
724 .in +2
725 .nf
726 example% x=2 ; printf "%f == %a\en" x x
727 .fi
728 .in -2
729 .sp
730
731 .sp
732 .LP
733 produces:
734
735 .sp
736 .in +2
737 .nf
738 2.000000 == 0x1.0000000000000000000000000000p+01
739 .fi
740 .in -2
741 .sp
742
743 .LP
744 \fBExample 8 \fROutput of unicode values
745 .sp
746 .LP
747 The following command will print the EURO unicode symbol (code-point 0x20ac).
748
749 .sp
750 .in +2
751 .nf
752 example% LC_ALL=en_US.UTF-8 printf "\u[20ac]\en"
753 .fi
754 .in -2
755 .sp
756
757 .sp
758 .LP
759 produces:
760
761 .sp
762 .in +2
763 .nf
764 <euro>
765 .fi
766 .in -2
767 .sp
768
769 .sp
770 .LP
771 where "<euro>" represents the EURO currency symbol character.
772
773 .LP
774 \fBExample 9 \fRConvert unicode character to unicode code-point value
775 .sp
776 .LP
777 The following command will print the hexadecimal value of a given character.
778
779 .sp
780 .in +2
781 .nf
782 example% export LC_ALL=en_US.UTF-8
783 example% printf "%x\en" "'<euro>"
784 .fi
785 .in -2
786 .sp
787
788 .sp
789 .LP
790 where "<euro>" represents the EURO currency symbol character (code-point
791 0x20ac).
792
793 .sp
794 .LP
795 produces:
796
797 .sp
798 .in +2
799 .nf
800 20ac
801 .fi
802 .in -2
803 .sp
804
805 .LP
806 \fBExample 10 \fRPrint the numeric value of an ASCII character
807 .sp
808 .in +2
809 .nf
810 example% printf "%d\en" "'A"
811 .fi
812 .in -2
813 .sp
814
815 .sp
816 .LP
817 produces:
818
819 .sp
820 .in +2
821 .nf
822 65
823 .fi
824 .in -2
825 .sp
826
827 .LP
828 \fBExample 11 \fRPrint the language-independent date and time format
829 .sp
830 .LP
831 To print the language-independent date and time format, the following statement
832 could be used:
833
834 .sp
835 .in +2
836 .nf
837 example% printf "format" weekday month day hour min
838 .fi
839 .in -2
840 .sp
841
842 .sp
843 .LP
844 For example,
845
846 .sp
847 .in +2
848 .nf
849 $ printf format "Sunday" "July" 3 10 2
850 .fi
851 .in -2
852 .sp
853
854 .sp
855 .LP
856 For American usage, format could be the string:
857
858 .sp
859 .in +2
860 .nf
861 "%s, %s %d, %d:%.2d\en"
862 .fi
863 .in -2
864 .sp
865
866 .sp
867 .LP
868 producing the message:
869
870 .sp
871 .in +2
872 .nf
873 Sunday, July 3, 10:02
874 .fi
875 .in -2
876 .sp
877
878 .sp
879 .LP
880 Whereas for EU usage, format could be the string:
881
882 .sp
883 .in +2
884 .nf
885 "%1$s, %3$d. %2$s, %4$d:%5$.2d\en"
886 .fi
887 .in -2
888 .sp
889
890 .sp
891 .LP
892 Note that the '$' characters must be properly escaped, such as
893
894 .sp
895 .in +2
896 .nf
897 "%1\e$s, %3\e$d. %2\e$s, %4\e$d:%5\e$.2d\en" in this case
898 .fi
899 .in -2
900 .sp
901
902 .sp
903 .LP
904 producing the message:
905
906 .sp
907 .in +2
908 .nf
909 Sunday, 3. July, 10:02
910 .fi
911 .in -2
912 .sp
913
914 .SH ENVIRONMENT VARIABLES
915 .sp
916 .LP
917 See \fBenviron\fR(5) for descriptions of the following environment variables
918 that affect the execution of \fBprintf\fR: \fBLANG\fR, \fBLC_ALL\fR,
919 \fBLC_CTYPE\fR, \fBLC_MESSAGES\fR, \fBLC_NUMERIC\fR, and \fBNLSPATH\fR.
920 .SH EXIT STATUS
921 .sp
922 .LP
923 The following exit values are returned:
924 .sp
925 .ne 2
926 .na
927 \fB\fB0\fR\fR
928 .ad
929 .RS 6n
930 Successful completion.
931 .RE
932
933 .sp
934 .ne 2
935 .na
936 \fB\fB>0\fR\fR
937 .ad
938 .RS 6n
939 An error occurred.
940 .RE
941
942 .SH ATTRIBUTES
943 .sp
944 .LP
945 See \fBattributes\fR(5) for descriptions of the following attributes:
946 .SS "/usr/bin/printf"
947 .sp
948
949 .sp
950 .TS
951 box;
952 c | c
953 l | l .
954 ATTRIBUTE TYPE ATTRIBUTE VALUE
955 _
956 CSI Enabled
957 _
958 Interface Stability Committed
959 _
960 Standard See \fBstandards\fR(5).
961 .TE
962
963 .SS "ksh93"
964 .sp
965
966 .sp
967 .TS
968 box;
969 c | c
970 l | l .
971 ATTRIBUTE TYPE ATTRIBUTE VALUE
972 _
973 Interface Stability Uncommitted
974 .TE
975
976 .SH SEE ALSO
977 .sp
978 .LP
979 \fBawk\fR(1), \fBbc\fR(1), \fBdate\fR(1), \fBecho\fR(1), \fBksh93\fR(1),
980 \fBprintf\fR(3C), \fBstrtod\fR(3C), \fBstrtol\fR(3C), \fBstrtoul\fR(3C),
981 \fBattributes\fR(5), \fBenviron\fR(5), \fBformats\fR(5), \fBstandards\fR(5)
982 .SH NOTES
983 .sp
984 .LP
985 Using format specifiers (characters following '%') which are not listed in the
986 \fBprintf\fR(3C) or this manual page will result in undefined behavior.
987 .sp
988 .LP
989 Using escape sequences (the character following a backslash ('\e')) which are
990 not listed in the \fBprintf\fR(3C) or this manual page will result in undefined
991 behavior.
992 .sp
993 .LP
994 Floating-point values follow C99, XPG6 and IEEE 754 standard behavior and can
995 handle values the same way as the platform's |\fBlong double\fR| datatype.
996 .sp
997 .LP
998 Floating-point values handle the sign separately which allows signs for values
999 like NaN (for example, -nan), Infinite (for example, -inf) and zero (for
1000 example, -0.0).