621 .sp
 622 .LP
 623 If an argument operand cannot be completely converted into an internal value
 624 appropriate to the corresponding conversion specification, a diagnostic message
 625 is written to standard error and the utility does exit with a zero exit status,
 626 but continues processing any remaining operands and writes the value
 627 accumulated at the time the error was detected to standard output.
 628 
 629 .LP
 630 \fBExample 6 \fRAlternative floating point representation 1
 631 .sp
 632 .LP
 633 The \fBprintf\fR utility supports an alternative floating point representation
 634 (see \fBprintf\fR(3C) entry for the "\fB%a\fR"/"\fB%A\fR"), which allows the
 635 output of floating-point values in a format that avoids the usual base16 to
 636 base10 rounding errors.
 637 
 638 .sp
 639 .in +2
 640 .nf
 641 example% printf "%a\n" 2 3.1 NaN
 642 .fi
 643 .in -2
 644 .sp
 645 
 646 .sp
 647 .LP
 648 produces:
 649 
 650 .sp
 651 .in +2
 652 .nf
 653 0x1.0000000000000000000000000000p+01
 654 0x1.8ccccccccccccccccccccccccccdp+01
 655 nan
 656 .fi
 657 .in -2
 658 .sp
 659 
 660 .LP
 661 \fBExample 7 \fRAlternative floating point representation 2
 662 .sp
 663 .LP
 664 The following example shows two different representations of the same
 665 floating-point value.
 666 
 667 .sp
 668 .in +2
 669 .nf
 670 example% x=2 ; printf "%f == %a\n" x x
 671 .fi
 672 .in -2
 673 .sp
 674 
 675 .sp
 676 .LP
 677 produces:
 678 
 679 .sp
 680 .in +2
 681 .nf
 682 2.000000 == 0x1.0000000000000000000000000000p+01
 683 .fi
 684 .in -2
 685 .sp
 686 
 687 .LP
 688 \fBExample 8 \fROutput of unicode values
 689 .sp
 690 .LP
 691 The following command will print the EURO unicode symbol (code-point 0x20ac).
 692 
 693 .sp
 694 .in +2
 695 .nf
 696 example% LC_ALL=en_US.UTF-8 printf "\u[20ac]\n"
 697 .fi
 698 .in -2
 699 .sp
 700 
 701 .sp
 702 .LP
 703 produces:
 704 
 705 .sp
 706 .in +2
 707 .nf
 708 <euro>
 709 .fi
 710 .in -2
 711 .sp
 712 
 713 .sp
 714 .LP
 715 where "<euro>" represents the EURO currency symbol character.
 716 
 717 .LP
 718 \fBExample 9 \fRConvert unicode character to unicode code-point value
 719 .sp
 720 .LP
 721 The following command will print the hexadecimal value of a given character.
 722 
 723 .sp
 724 .in +2
 725 .nf
 726 example% export LC_ALL=en_US.UTF-8
 727 example% printf "%x\n" "'<euro>"
 728 .fi
 729 .in -2
 730 .sp
 731 
 732 .sp
 733 .LP
 734 where "<euro>" represents the EURO currency symbol character (code-point
 735 0x20ac).
 736 
 737 .sp
 738 .LP
 739 produces:
 740 
 741 .sp
 742 .in +2
 743 .nf
 744 20ac
 745 .fi
 746 .in -2
 747 .sp
 748 
 749 .LP
 750 \fBExample 10 \fRPrint the numeric value of an ASCII character
 751 .sp
 752 .in +2
 753 .nf
 754 example% printf "%d\n" "'A"
 755 .fi
 756 .in -2
 757 .sp
 758 
 759 .sp
 760 .LP
 761 produces:
 762 
 763 .sp
 764 .in +2
 765 .nf
 766 65
 767 .fi
 768 .in -2
 769 .sp
 770 
 771 .LP
 772 \fBExample 11 \fRPrint the language-independent date and time format
 773 .sp
 774 .LP

 785 
 786 .sp
 787 .LP
 788 For example,
 789 
 790 .sp
 791 .in +2
 792 .nf
 793 $ printf format "Sunday" "July" 3 10 2
 794 .fi
 795 .in -2
 796 .sp
 797 
 798 .sp
 799 .LP
 800 For American usage, format could be the string:
 801 
 802 .sp
 803 .in +2
 804 .nf
 805 "%s, %s %d, %d:%.2d\n"
 806 .fi
 807 .in -2
 808 .sp
 809 
 810 .sp
 811 .LP
 812 producing the message:
 813 
 814 .sp
 815 .in +2
 816 .nf
 817 Sunday, July 3, 10:02
 818 .fi
 819 .in -2
 820 .sp
 821 
 822 .sp
 823 .LP
 824 Whereas for EU usage, format could be the string:
 825 
 826 .sp
 827 .in +2
 828 .nf
 829 "%1$s, %3$d. %2$s, %4$d:%5$.2d\n"
 830 .fi
 831 .in -2
 832 .sp
 833 
 834 .sp
 835 .LP
 836 Note that the '$' characters must be properly escaped, such as
 837 
 838 .sp
 839 .in +2
 840 .nf
 841 "%1\$s, %3\$d. %2\$s, %4\$d:%5\$.2d\n" in this case
 842 .fi
 843 .in -2
 844 .sp
 845 
 846 .sp
 847 .LP
 848 producing the message:
 849 
 850 .sp
 851 .in +2
 852 .nf
 853 Sunday, 3. July, 10:02
 854 .fi
 855 .in -2
 856 .sp
 857 
 858 .SH ENVIRONMENT VARIABLES
 859 .sp
 860 .LP
 861 See \fBenviron\fR(5) for descriptions of the following environment variables

 913 c | c
 914 l | l .
 915 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 916 _
 917 Interface Stability     Uncommitted
 918 .TE
 919 
 920 .SH SEE ALSO
 921 .sp
 922 .LP
 923 \fBawk\fR(1), \fBbc\fR(1), \fBdate\fR(1), \fBecho\fR(1), \fBksh93\fR(1),
 924 \fBprintf\fR(3C), \fBstrtod\fR(3C), \fBstrtol\fR(3C), \fBstrtoul\fR(3C),
 925 \fBattributes\fR(5), \fBenviron\fR(5), \fBformats\fR(5), \fBstandards\fR(5)
 926 .SH NOTES
 927 .sp
 928 .LP
 929 Using format specifiers (characters following '%') which are not listed in the
 930 \fBprintf\fR(3C) or this manual page will result in undefined behavior.
 931 .sp
 932 .LP
 933 Using escape sequences (the character following a backslash ('\')) which are
 934 not listed in the \fBprintf\fR(3C) or this manual page will result in undefined
 935 behavior.
 936 .sp
 937 .LP
 938 Floating-point values follow C99, XPG6 and IEEE 754 standard behavior and can
 939 handle values the same way as the platform's |\fBlong double\fR| datatype.
 940 .sp
 941 .LP
 942 Floating-point values handle the sign separately which allows signs for values
 943 like NaN (for example, -nan), Infinite (for example, -inf) and zero (for
 944 example, -0.0).

 621 .sp
 622 .LP
 623 If an argument operand cannot be completely converted into an internal value
 624 appropriate to the corresponding conversion specification, a diagnostic message
 625 is written to standard error and the utility does exit with a zero exit status,
 626 but continues processing any remaining operands and writes the value
 627 accumulated at the time the error was detected to standard output.
 628 
 629 .LP
 630 \fBExample 6 \fRAlternative floating point representation 1
 631 .sp
 632 .LP
 633 The \fBprintf\fR utility supports an alternative floating point representation
 634 (see \fBprintf\fR(3C) entry for the "\fB%a\fR"/"\fB%A\fR"), which allows the
 635 output of floating-point values in a format that avoids the usual base16 to
 636 base10 rounding errors.
 637 
 638 .sp
 639 .in +2
 640 .nf
 641 example% printf "%a\en" 2 3.1 NaN
 642 .fi
 643 .in -2
 644 .sp
 645 
 646 .sp
 647 .LP
 648 produces:
 649 
 650 .sp
 651 .in +2
 652 .nf
 653 0x1.0000000000000000000000000000p+01
 654 0x1.8ccccccccccccccccccccccccccdp+01
 655 nan
 656 .fi
 657 .in -2
 658 .sp
 659 
 660 .LP
 661 \fBExample 7 \fRAlternative floating point representation 2
 662 .sp
 663 .LP
 664 The following example shows two different representations of the same
 665 floating-point value.
 666 
 667 .sp
 668 .in +2
 669 .nf
 670 example% x=2 ; printf "%f == %a\en" x x
 671 .fi
 672 .in -2
 673 .sp
 674 
 675 .sp
 676 .LP
 677 produces:
 678 
 679 .sp
 680 .in +2
 681 .nf
 682 2.000000 == 0x1.0000000000000000000000000000p+01
 683 .fi
 684 .in -2
 685 .sp
 686 
 687 .LP
 688 \fBExample 8 \fROutput of unicode values
 689 .sp
 690 .LP
 691 The following command will print the EURO unicode symbol (code-point 0x20ac).
 692 
 693 .sp
 694 .in +2
 695 .nf
 696 example% LC_ALL=en_US.UTF-8 printf "\u[20ac]\en"
 697 .fi
 698 .in -2
 699 .sp
 700 
 701 .sp
 702 .LP
 703 produces:
 704 
 705 .sp
 706 .in +2
 707 .nf
 708 <euro>
 709 .fi
 710 .in -2
 711 .sp
 712 
 713 .sp
 714 .LP
 715 where "<euro>" represents the EURO currency symbol character.
 716 
 717 .LP
 718 \fBExample 9 \fRConvert unicode character to unicode code-point value
 719 .sp
 720 .LP
 721 The following command will print the hexadecimal value of a given character.
 722 
 723 .sp
 724 .in +2
 725 .nf
 726 example% export LC_ALL=en_US.UTF-8
 727 example% printf "%x\en" "'<euro>"
 728 .fi
 729 .in -2
 730 .sp
 731 
 732 .sp
 733 .LP
 734 where "<euro>" represents the EURO currency symbol character (code-point
 735 0x20ac).
 736 
 737 .sp
 738 .LP
 739 produces:
 740 
 741 .sp
 742 .in +2
 743 .nf
 744 20ac
 745 .fi
 746 .in -2
 747 .sp
 748 
 749 .LP
 750 \fBExample 10 \fRPrint the numeric value of an ASCII character
 751 .sp
 752 .in +2
 753 .nf
 754 example% printf "%d\en" "'A"
 755 .fi
 756 .in -2
 757 .sp
 758 
 759 .sp
 760 .LP
 761 produces:
 762 
 763 .sp
 764 .in +2
 765 .nf
 766 65
 767 .fi
 768 .in -2
 769 .sp
 770 
 771 .LP
 772 \fBExample 11 \fRPrint the language-independent date and time format
 773 .sp
 774 .LP

 785 
 786 .sp
 787 .LP
 788 For example,
 789 
 790 .sp
 791 .in +2
 792 .nf
 793 $ printf format "Sunday" "July" 3 10 2
 794 .fi
 795 .in -2
 796 .sp
 797 
 798 .sp
 799 .LP
 800 For American usage, format could be the string:
 801 
 802 .sp
 803 .in +2
 804 .nf
 805 "%s, %s %d, %d:%.2d\en"
 806 .fi
 807 .in -2
 808 .sp
 809 
 810 .sp
 811 .LP
 812 producing the message:
 813 
 814 .sp
 815 .in +2
 816 .nf
 817 Sunday, July 3, 10:02
 818 .fi
 819 .in -2
 820 .sp
 821 
 822 .sp
 823 .LP
 824 Whereas for EU usage, format could be the string:
 825 
 826 .sp
 827 .in +2
 828 .nf
 829 "%1$s, %3$d. %2$s, %4$d:%5$.2d\en"
 830 .fi
 831 .in -2
 832 .sp
 833 
 834 .sp
 835 .LP
 836 Note that the '$' characters must be properly escaped, such as
 837 
 838 .sp
 839 .in +2
 840 .nf
 841 "%1\$s, %3\$d. %2\$s, %4\$d:%5\$.2d\en" in this case
 842 .fi
 843 .in -2
 844 .sp
 845 
 846 .sp
 847 .LP
 848 producing the message:
 849 
 850 .sp
 851 .in +2
 852 .nf
 853 Sunday, 3. July, 10:02
 854 .fi
 855 .in -2
 856 .sp
 857 
 858 .SH ENVIRONMENT VARIABLES
 859 .sp
 860 .LP
 861 See \fBenviron\fR(5) for descriptions of the following environment variables

 913 c | c
 914 l | l .
 915 ATTRIBUTE TYPE  ATTRIBUTE VALUE
 916 _
 917 Interface Stability     Uncommitted
 918 .TE
 919 
 920 .SH SEE ALSO
 921 .sp
 922 .LP
 923 \fBawk\fR(1), \fBbc\fR(1), \fBdate\fR(1), \fBecho\fR(1), \fBksh93\fR(1),
 924 \fBprintf\fR(3C), \fBstrtod\fR(3C), \fBstrtol\fR(3C), \fBstrtoul\fR(3C),
 925 \fBattributes\fR(5), \fBenviron\fR(5), \fBformats\fR(5), \fBstandards\fR(5)
 926 .SH NOTES
 927 .sp
 928 .LP
 929 Using format specifiers (characters following '%') which are not listed in the
 930 \fBprintf\fR(3C) or this manual page will result in undefined behavior.
 931 .sp
 932 .LP
 933 Using escape sequences (the character following a backslash ('\e')) which are
 934 not listed in the \fBprintf\fR(3C) or this manual page will result in undefined
 935 behavior.
 936 .sp
 937 .LP
 938 Floating-point values follow C99, XPG6 and IEEE 754 standard behavior and can
 939 handle values the same way as the platform's |\fBlong double\fR| datatype.
 940 .sp
 941 .LP
 942 Floating-point values handle the sign separately which allows signs for values
 943 like NaN (for example, -nan), Infinite (for example, -inf) and zero (for
 944 example, -0.0).