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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 | --- printf.3.orig 2009-12-15 17:50:20.000000000 -0800 +++ printf.3 2009-12-15 17:58:46.000000000 -0800 @@ -42,7 +42,6 @@ .Sh LIBRARY .Lb libc .Sh SYNOPSIS -.Fd "#define _WITH_DPRINTF" .In stdio.h .Ft int .Fn printf "const char * restrict format" ... @@ -98,7 +97,7 @@ write output to the given file descripto and .Fn vsnprintf write to the character string -.Fa str ; +.Fa s ; and .Fn asprintf and @@ -106,6 +105,12 @@ and dynamically allocate a new string with .Xr malloc 3 . .Pp +Extended locale versions of these functions are documented in +.Xr printf_l 3 . +See +.Xr xlocale 3 +for more information. +.Pp These functions write the output under the control of a .Fa format string that specifies how subsequent arguments @@ -122,7 +127,7 @@ except for and .Fn vsnprintf , which return the number of characters that would have been printed if the -.Fa size +.Fa n were unlimited (again, not including the final .Ql \e0 ) . @@ -154,14 +159,14 @@ and .Fn vsnprintf functions will write at most -.Fa size Ns \-1 +.Fa n Ns \-1 of the characters printed into the output string (the -.Fa size Ns 'th +.Fa n Ns \'th character then gets the terminating .Ql \e0 ) ; if the return value is greater than or equal to the -.Fa size +.Fa n argument, the string was too short and some of the printed characters were discarded. The output is always null-terminated. @@ -172,7 +177,11 @@ and .Fn vsprintf functions effectively assume an infinite -.Fa size . +.Fa n . +.Pp +For those routines that write to a user-provided character string, +that string and the format strings should not overlap, as the +behavior is undefined. .Pp The format string is composed of zero or more directives: ordinary @@ -291,6 +300,20 @@ the non-monetary separator returned by .Xr localeconv 3 . .El .It +An optional separator character ( +.Cm \ , | \; | \ : | _ +) used for separating multiple values when printing an AltiVec or SSE vector, +or other multi-value unit. +.Pp +NOTE: This is an extension to the +.Fn printf +specification. +Behaviour of these values for +.Fn printf +is only defined for operating systems conforming to the +AltiVec Technology Programming Interface Manual. +(At time of writing this includes only Mac OS X 10.2 and later.) +.It An optional decimal digit string specifying a minimum field width. If the converted value has fewer characters than the field width, it will be padded with spaces on the left (or right, if the left-adjustment @@ -383,6 +406,34 @@ conversion: .It Sy Modifier Ta Cm c Ta Cm s .It Cm l No (ell) Ta Vt wint_t Ta Vt "wchar_t *" .El +.Pp +The AltiVec Technology Programming Interface Manual also defines five additional length modifiers +which can be used (in place of the conventional length modifiers) for the printing of AltiVec or SSE vectors: +.Bl -tag -compact +.It Cm v +Treat the argument as a vector value, unit length will be determined by the conversion +specifier (default = 16 8-bit units for all integer conversions, +4 32-bit units for floating point conversions). +.It Cm vh, hv +Treat the argument as a vector of 8 16-bit units. +.It Cm vl, lv +Treat the argument as a vector of 4 32-bit units. +.El +.Pp +NOTE: The vector length specifiers are extensions to the +.Fn printf +specification. +Behaviour of these values for +.Fn printf +is only defined for operating systems conforming to the +AltiVec Technology Programming Interface Manual. +(At time of writing this includes only Mac OS X 10.2 and later.) +.Pp +As a further extension, for SSE2 64-bit units: +.Bl -tag -compact +.It Cm vll, llv +Treat the argument as a vector of 2 64-bit units. +.El .It A character that specifies the type of conversion to be applied. .El @@ -561,10 +612,9 @@ For example, and .Li 0xc.9p-2 are all equivalent. -.Fx 8.0 -and later always prints finite non-zero numbers using -.Ql 1 -as the digit before the hexadecimal point. +The format chosen depends on the internal representation of the +number, but the implementation guarantees that the length of the +mantissa will be minimized. Zeroes are always represented with a mantissa of 0 (preceded by a .Ql - if appropriate) and an exponent of @@ -781,34 +831,6 @@ Always use the proper secure idiom: .Pp .Dl "snprintf(buffer, sizeof(buffer), \*q%s\*q, string);" .Sh COMPATIBILITY -Many application writers used the name -.Va dprintf -before the -.Fn dprintf -function was introduced in -.St -p1003.1 , -so a prototype is not provided by default in order to avoid -compatibility problems. -Applications that wish to use the -.Fn dprintf -function described herein should either request a strict -.St -p1003.1-2008 -environment by defining the macro -.Dv _POSIX_C_SOURCE -to the value 200809 or greater, or by defining the macro -.Dv _WITH_DPRINTF , -prior to the inclusion of -.In stdio.h . -For compatibility with GNU libc, defining either -.Dv _BSD_SOURCE -or -.Dv _GNU_SOURCE -prior to the inclusion of -.In stdio.h -will also make -.Fn dprintf -available. -.Pp The conversion formats .Cm \&%D , \&%O , and @@ -845,9 +867,11 @@ Insufficient storage space is available. .El .Sh SEE ALSO .Xr printf 1 , +.Xr printf_l 3 , .Xr fmtcheck 3 , .Xr scanf 3 , .Xr setlocale 3 , +.Xr stdarg 3 , .Xr wprintf 3 .Sh STANDARDS Subject to the caveats noted in the |