Eric Lowe wrote on Tue, 10 Oct 2006 12:31:31 -0500... >> DESCRIPTION >> The humanize_number() function will convert the signed integer >> <value> to a string, which will write at most <buf_len> bytes >> to the output <buffer>. The format of the output string >> is described by the <fmt> string. >> >> Conversion Specification >> The <fmt> string determines how <value> will be formatted to >> the output in a fashion similar to sprintf(). Each conversion >> specifier within the string consists of the % character, after >> which the following appear in sequence:
Why is there no way to request that a % character be included in the output. >> >> o One or more of the following modifiers: Did you mean "Zero or more" rather than "One or more"? Most of the examples don't contain any modifiers. >> '0' : the resulting string is zero padded. >> '-' : the resulting string is left aligned. >> '+' : the resulting string's first char is a >> '+' if result is greater than zero. >> ' ' : the resulting string's first char is a >> space is the result is greater than zero; >> used only if the '+' modifier is not >> defined. >> '#' : suppress trailing zeroes. Why is there no way to specify use of the thousands' grouping character on output? >> o An optional decimal length. If the result is smaller, >> the output will be padded according to the modifiers >> if present, otherwise the result will be space-padded. If no length is specified, why is there any padding? Most of the examples don't show padding characters even though this says spaces will be added??? >> o An optional decimal precision, expressed as .# where >> # is an unsigned decimal integer. When not specified, >> three digits is the default precision. Am I correct in assuming that .0 also suppresses the radix character? Am I also correct in assuming that if the # modifier above causes all zero characters after the radix character to be suppressed the radix character will also be suppressed? >> o An optional 'b' character, which will express the result >> as radix-2 rather than radix-10 (radix 2 uses 1024^N >> whereas the default of radix 10 uses 1000^N to convert >> the number). >> o An optional unit character, from the following set: >> 'A' : the unit is choosen automatically for the best >> human-readable result. The integer part of the >> result will be between 0 and 999 when radix-10 >> is used for the conversion, or 0 to 1023 when >> radix-2 is used for the conversion. >> 'N' : use no metric unit for conversion. >> 'K' : use the metric unit of kilo. >> 'M' : use the metric unit of mega. >> 'G' : use the metric unit of giga. >> 'P' : use the metric unit of peta. >> 'T' : use the metric unit of tera. >> 'E' : use the metric unit of exa. Shouldn't you also specify lowercase versions of these unit characters to produce lowercase characters in the output? >> >> RETURN VALUE >> The humanize_number() function returns the number of bytes >> written into <buffer> if less than or equal to <buf_len>, >> otherwise returns the number of bytes that would have been >> written to <buffer> if <buf_len> had been sufficiently large. >> The value of <buf_len> may be passed as zero, and/or <buffer> >> may be a null pointer; this will result in a return value of >> the minimal-length buffer required to contain a complete >> result (minus a terminating NUL character). Am I correct in assuming that you mean "not including the" rather than the mathematical operation of subtracting zero stated by "minus a"? (I.e., if I want to use the return value as an argument to malloc(), I need to add 1 to actually get a minimal-length buffer big enough to contain a complete result including the terminating '\0' character?) What goes into <buffer> if <buf_len> bytes aren't sufficient to hold the resulting string? >> >> EXAMPLES >> humanize_number(123456789, "%5M", buffer, len) >> will output "123.457M" into the buffer >> >> humanize_number(123456789, "%5.M", buffer, len) According to the spec above, this format is not legal (M is not an unsigned decimal number). >> will output " 123M" into the buffer >> >> humanize_number(123456789, "%5.0M", buffer, len) >> will output " 123M" into the buffer Why is there a leading space in the example above, but no leading space in the examples below? Note that most of the issues raised above would already be covered if you added a flag or modifier character (or two) to the *printf and *scanf function families of functions' format strings. I'm not convinced by your argument so far that we couldn't find anything (like 'm' or 'M' for metric) to be used with signed and unsigned decimal, octal, and hexadecimal conversions. With a little bit of research, I'd be surprised if the project team couldn't make a proposal that would be accepted by "the standards community" with no conflicts with other existing practice. >> >> humanize_number(123456789, "%5.1M", buffer, len) >> will output "123.5M" into the buffer >> >> humanize_number(123456789, "%5.2M", buffer, len) >> will output "123.46M" into the buffer ... ... ...
