. ie !"\$2"" .TP \n()Cu
. el .TP 15
\$1 \\$2\ (\$3)
\$1 \\$2\ .\} \\$1\ .\} .\} .. ..
\h'-1.5n'\L'|\n(^yu-1v'\l'\n(^lu+3n\(ul'\L'\n(^tu+1v-\n(^yu'\l'|0u-1.5n\(ul' .\} \h'-1.5n'\L'|\n(^yu-1v'\h'\n(^lu+3n'\L'\n(^tu+1v-\n(^yu'\l'|0u-1.5n\(ul' .\} .\}
\h'|\n(^lu+3n'\L'|\n(^Yu-1v\(bv'\v'\n(^tu+1v-\n(^Yu'\h'-|\n(^lu+3n'.\} .. 'ti 0 'nf .\} \kx\h'-\nxu'\h'|\n(^lu+3n'\ky\L'-\n(^xu'\v'\n(^xu'\h'|0u'\c .\} 'fi .\} .\} ..
See the \options\ manual entry for details on the standard options. ..
Command-Line Name: \\$1\ Database Name: \\$2\ Database Class: \\$3\
.. \$1\l'|0\(ul'\$2 ....
This command parses fields from an input string in the same fashion as the ANSI C sscanf procedure and returns a count of the number of conversions performed, or -1 if the end of the input string is reached before any conversions have been performed. String gives the input to be parsed and format indicates how to parse it, using % conversion specifiers as in sscanf. Each varName gives the name of a variable; when a field is scanned from string the result is converted back into a string and assigned to the corresponding variable. If no varName variables are specified, then scan works in an inline manner, returning the data that would otherwise be stored in the variables as a list. In the inline case, an empty string is returned when the end of the input string is reached before any conversions have been performed.
Scan operates by scanning string and format together. If the next character in format is a blank or tab then it matches any number of white space characters in string (including zero). Otherwise, if it isn't a % character then it must match the next character of string. When a % is encountered in format, it indicates the start of a conversion specifier. A conversion specifier contains up to four fields after the %: a *, which indicates that the converted value is to be discarded instead of assigned to a variable; a XPG3 position specifier; a number indicating a maximum field width; and a conversion character. All of these fields are optional except for the conversion character. The fields that are present must appear in the order given above.
When scan finds a conversion specifier in format, it first skips any white-space characters in string (unless the specifier is [ or c). Then it converts the next input characters according to the conversion specifier and stores the result in the variable given by the next argument to scan.
If the % is followed by a decimal number and a $, as in ``%2$d'', then the variable to use is not taken from the next sequential argument. Instead, it is taken from the argument indicated by the number, where 1 corresponds to the first varName. If there are any positional specifiers in format then all of the specifiers must be positional. Every varName on the argument list must correspond to exactly one conversion specifier or an error is generated, or in the inline case, any position can be specified at most once and the empty positions will be filled in with empty strings.
The following conversion characters are supported:
The number of characters read from the input for a conversion is the largest number that makes sense for that particular conversion (e.g. as many decimal digits as possible for %d, as many octal digits as possible for %o, and so on). The input field for a given conversion terminates either when a white-space character is encountered or when the maximum field width has been reached, whichever comes first. If a * is present in the conversion specifier then no variable is assigned and the next scan argument is not consumed.
The behavior of the scan command is the same as the behavior of the ANSI C sscanf procedure except for the following differences:
%p conversion specifier is not currently supported.
For %c conversions a single character value is converted to a decimal string, which is then assigned to the corresponding varName; no field width may be specified for this conversion.
The l, h, and L modifiers are ignored; integer values are always converted as if there were no modifier present and real values are always converted as if the l modifier were present (i.e. type double is used for the internal representation).
If the end of the input string is reached before any conversions have been performed and no variables are given, and empty string is returned.