Formats date according to the directives in the given format string. The directives begin with a percent (%) character. Any text not listed as a directive will be passed through to the output string.
A directive consists of a percent (%) character, zero or more flags, an optional minimum field width, an optional modifier, and a conversion specifier as follows.
%<flags><width><modifier><conversion>
Flags:
- don't pad a numerical output. _ use spaces for padding. 0 use zeros for padding. ^ upcase the result string. # change case. : use colons for %z.
The minimum field width specifies the minimum width.
The modifiers are “E” and “O”. They are ignored.
Format directives:
Date (Year, Month, Day):
%Y - Year with century (can be negative, 4 digits at least)
-0001, 0000, 1995, 2009, 14292, etc.
%C - year / 100 (round down. 20 in 2009)
%y - year % 100 (00..99)
%m - Month of the year, zero-padded (01..12)
%_m blank-padded ( 1..12)
%-m no-padded (1..12)
%B - The full month name (``January'')
%^B uppercased (``JANUARY'')
%b - The abbreviated month name (``Jan'')
%^b uppercased (``JAN'')
%h - Equivalent to %b
%d - Day of the month, zero-padded (01..31)
%-d no-padded (1..31)
%e - Day of the month, blank-padded ( 1..31)
%j - Day of the year (001..366)
Time (Hour, Minute, Second, Subsecond):
%H - Hour of the day, 24-hour clock, zero-padded (00..23)
%k - Hour of the day, 24-hour clock, blank-padded ( 0..23)
%I - Hour of the day, 12-hour clock, zero-padded (01..12)
%l - Hour of the day, 12-hour clock, blank-padded ( 1..12)
%P - Meridian indicator, lowercase (``am'' or ``pm'')
%p - Meridian indicator, uppercase (``AM'' or ``PM'')
%M - Minute of the hour (00..59)
%S - Second of the minute (00..60)
%L - Millisecond of the second (000..999)
%N - Fractional seconds digits, default is 9 digits (nanosecond)
%3N millisecond (3 digits) %15N femtosecond (15 digits)
%6N microsecond (6 digits) %18N attosecond (18 digits)
%9N nanosecond (9 digits) %21N zeptosecond (21 digits)
%12N picosecond (12 digits) %24N yoctosecond (24 digits)
Time zone:
%z - Time zone as hour and minute offset from UTC (e.g. +0900)
%:z - hour and minute offset from UTC with a colon (e.g. +09:00)
%::z - hour, minute and second offset from UTC (e.g. +09:00:00)
%:::z - hour, minute and second offset from UTC
(e.g. +09, +09:30, +09:30:30)
%Z - Equivalent to %:z (e.g. +09:00)
Weekday:
%A - The full weekday name (``Sunday'')
%^A uppercased (``SUNDAY'')
%a - The abbreviated name (``Sun'')
%^a uppercased (``SUN'')
%u - Day of the week (Monday is 1, 1..7)
%w - Day of the week (Sunday is 0, 0..6)
ISO 8601 week-based year and week number:
The week 1 of YYYY starts with a Monday and includes YYYY-01-04.
The days in the year before the first week are in the last week of
the previous year.
%G - The week-based year
%g - The last 2 digits of the week-based year (00..99)
%V - Week number of the week-based year (01..53)
Week number:
The week 1 of YYYY starts with a Sunday or Monday (according to %U
or %W). The days in the year before the first week are in week 0.
%U - Week number of the year. The week starts with Sunday. (00..53)
%W - Week number of the year. The week starts with Monday. (00..53)
Seconds since the Unix Epoch:
%s - Number of seconds since 1970-01-01 00:00:00 UTC.
%Q - Number of milliseconds since 1970-01-01 00:00:00 UTC.
Literal string:
%n - Newline character (\n)
%t - Tab character (\t)
%% - Literal ``%'' character
Combination:
%c - date and time (%a %b %e %T %Y)
%D - Date (%m/%d/%y)
%F - The ISO 8601 date format (%Y-%m-%d)
%v - VMS date (%e-%b-%Y)
%x - Same as %D
%X - Same as %T
%r - 12-hour time (%I:%M:%S %p)
%R - 24-hour time (%H:%M)
%T - 24-hour time (%H:%M:%S)
%+ - date(1) (%a %b %e %H:%M:%S %Z %Y)
This method is similar to the strftime() function defined in ISO C and POSIX. Several directives (%a, %A, %b, %B, %c, %p, %r, %x, %X, %E*, %O* and %Z) are locale dependent in the function. However, this method is locale independent. So, the result may differ even if the same format string is used in other systems such as C. It is good practice to avoid %x and %X because there are corresponding locale independent representations, %D and %T.
Examples:
d = DateTime.new(2007,11,19,8,37,48,"-06:00") #=> #<DateTime: 2007-11-19T08:37:48-0600 ...> d.strftime("Printed on %m/%d/%Y") #=> "Printed on 11/19/2007" d.strftime("at %I:%M%p") #=> "at 08:37AM"
Various ISO 8601 formats:
%Y%m%d => 20071119 Calendar date (basic) %F => 2007-11-19 Calendar date (extended) %Y-%m => 2007-11 Calendar date, reduced accuracy, specific month %Y => 2007 Calendar date, reduced accuracy, specific year %C => 20 Calendar date, reduced accuracy, specific century %Y%j => 2007323 Ordinal date (basic) %Y-%j => 2007-323 Ordinal date (extended) %GW%V%u => 2007W471 Week date (basic) %G-W%V-%u => 2007-W47-1 Week date (extended) %GW%V => 2007W47 Week date, reduced accuracy, specific week (basic) %G-W%V => 2007-W47 Week date, reduced accuracy, specific week (extended) %H%M%S => 083748 Local time (basic) %T => 08:37:48 Local time (extended) %H%M => 0837 Local time, reduced accuracy, specific minute (basic) %H:%M => 08:37 Local time, reduced accuracy, specific minute (extended) %H => 08 Local time, reduced accuracy, specific hour %H%M%S,%L => 083748,000 Local time with decimal fraction, comma as decimal sign (basic) %T,%L => 08:37:48,000 Local time with decimal fraction, comma as decimal sign (extended) %H%M%S.%L => 083748.000 Local time with decimal fraction, full stop as decimal sign (basic) %T.%L => 08:37:48.000 Local time with decimal fraction, full stop as decimal sign (extended) %H%M%S%z => 083748-0600 Local time and the difference from UTC (basic) %T%:z => 08:37:48-06:00 Local time and the difference from UTC (extended) %Y%m%dT%H%M%S%z => 20071119T083748-0600 Date and time of day for calendar date (basic) %FT%T%:z => 2007-11-19T08:37:48-06:00 Date and time of day for calendar date (extended) %Y%jT%H%M%S%z => 2007323T083748-0600 Date and time of day for ordinal date (basic) %Y-%jT%T%:z => 2007-323T08:37:48-06:00 Date and time of day for ordinal date (extended) %GW%V%uT%H%M%S%z => 2007W471T083748-0600 Date and time of day for week date (basic) %G-W%V-%uT%T%:z => 2007-W47-1T08:37:48-06:00 Date and time of day for week date (extended) %Y%m%dT%H%M => 20071119T0837 Calendar date and local time (basic) %FT%R => 2007-11-19T08:37 Calendar date and local time (extended) %Y%jT%H%MZ => 2007323T0837Z Ordinal date and UTC of day (basic) %Y-%jT%RZ => 2007-323T08:37Z Ordinal date and UTC of day (extended) %GW%V%uT%H%M%z => 2007W471T0837-0600 Week date and local time and difference from UTC (basic) %G-W%V-%uT%R%:z => 2007-W47-1T08:37-06:00 Week date and local time and difference from UTC (extended)
See also strftime(3) and ::strptime.
Takes a string representation of a Time and attempts to parse it using a heuristic.
require 'time' Time.parse("2010-10-31") #=> 2010-10-31 00:00:00 -0500
Any missing pieces of the date are inferred based on the current date.
require 'time' # assuming the current date is "2011-10-31" Time.parse("12:00") #=> 2011-10-31 12:00:00 -0500
We can change the date used to infer our missing elements by passing a second object that responds to mon, day and year, such as Date, Time or DateTime. We can also use our own object.
require 'time' class MyDate attr_reader :mon, :day, :year def initialize(mon, day, year) @mon, @day, @year = mon, day, year end end d = Date.parse("2010-10-28") t = Time.parse("2010-10-29") dt = DateTime.parse("2010-10-30") md = MyDate.new(10,31,2010) Time.parse("12:00", d) #=> 2010-10-28 12:00:00 -0500 Time.parse("12:00", t) #=> 2010-10-29 12:00:00 -0500 Time.parse("12:00", dt) #=> 2010-10-30 12:00:00 -0500 Time.parse("12:00", md) #=> 2010-10-31 12:00:00 -0500
If a block is given, the year described in date is converted by the block. This is specifically designed for handling two digit years. For example, if you wanted to treat all two digit years prior to 70 as the year 2000+ you could write this:
require 'time' Time.parse("01-10-31") {|year| year + (year < 70 ? 2000 : 1900)} #=> 2001-10-31 00:00:00 -0500 Time.parse("70-10-31") {|year| year + (year < 70 ? 2000 : 1900)} #=> 1970-10-31 00:00:00 -0500
If the upper components of the given time are broken or missing, they are supplied with those of now. For the lower components, the minimum values (1 or 0) are assumed if broken or missing. For example:
require 'time' # Suppose it is "Thu Nov 29 14:33:20 2001" now and # your time zone is EST which is GMT-5. now = Time.parse("Thu Nov 29 14:33:20 2001") Time.parse("16:30", now) #=> 2001-11-29 16:30:00 -0500 Time.parse("7/23", now) #=> 2001-07-23 00:00:00 -0500 Time.parse("Aug 31", now) #=> 2001-08-31 00:00:00 -0500 Time.parse("Aug 2000", now) #=> 2000-08-01 00:00:00 -0500
Since there are numerous conflicts among locally defined time zone abbreviations all over the world, this method is not intended to understand all of them. For example, the abbreviation “CST” is used variously as:
-06:00 in America/Chicago, -05:00 in America/Havana, +08:00 in Asia/Harbin, +09:30 in Australia/Darwin, +10:30 in Australia/Adelaide, etc.
Based on this fact, this method only understands the time zone abbreviations described in RFC 822 and the system time zone, in the order named. (i.e. a definition in RFC 822 overrides the system time zone definition.) The system time zone is taken from Time.local(year, 1, 1).zone and Time.local(year, 7, 1).zone. If the extracted time zone abbreviation does not match any of them, it is ignored and the given time is regarded as a local time.
ArgumentError is raised if Date._parse cannot extract information from date or if the Time class cannot represent specified date.
This method can be used as a fail-safe for other parsing methods as:
Time.rfc2822(date) rescue Time.parse(date) Time.httpdate(date) rescue Time.parse(date) Time.xmlschema(date) rescue Time.parse(date)
A failure of Time.parse should be checked, though.
You must require ‘time’ to use this method.
Works similar to parse except that instead of using a heuristic to detect the format of the input string, you provide a second argument that describes the format of the string.
If a block is given, the year described in date is converted by the block. For example:
Time.strptime(...) {|y| y < 100 ? (y >= 69 ? y + 1900 : y + 2000) : y}
Below is a list of the formatting options:
The abbreviated weekday name (“Sun”)
The full weekday name (“Sunday”)
The abbreviated month name (“Jan”)
The full month name (“January”)
The preferred local date and time representation
Century (20 in 2009)
Day of the month (01..31)
Date (%m/%d/%y)
Day of the month, blank-padded ( 1..31)
Equivalent to %Y-%m-%d (the ISO 8601 date format)
Equivalent to %b
Hour of the day, 24-hour clock (00..23)
Hour of the day, 12-hour clock (01..12)
Day of the year (001..366)
hour, 24-hour clock, blank-padded ( 0..23)
hour, 12-hour clock, blank-padded ( 0..12)
Millisecond of the second (000..999)
Month of the year (01..12)
Minute of the hour (00..59)
Newline (n)
Fractional seconds digits
Meridian indicator (“AM” or “PM”)
Meridian indicator (“am” or “pm”)
Number of milliseconds since 1970-01-01 00:00:00 UTC.
time, 12-hour (same as %I:%M:%S %p)
time, 24-hour (%H:%M)
Number of seconds since 1970-01-01 00:00:00 UTC.
Second of the minute (00..60)
Tab character (t)
time, 24-hour (%H:%M:%S)
Day of the week as a decimal, Monday being 1. (1..7)
Week number of the current year, starting with the first Sunday as the first day of the first week (00..53)
VMS date (%e-%b-%Y)
Week number of year according to ISO 8601 (01..53)
Week number of the current year, starting with the first Monday as the first day of the first week (00..53)
Day of the week (Sunday is 0, 0..6)
Preferred representation for the date alone, no time
Preferred representation for the time alone, no date
Year without a century (00..99)
Year which may include century, if provided
Time zone as hour offset from UTC (e.g. +0900)
Time zone name
Literal “%” character
date(1) (%a %b %e %H:%M:%S %Z %Y)
require 'time' Time.strptime("2000-10-31", "%Y-%m-%d") #=> 2000-10-31 00:00:00 -0500
You must require ‘time’ to use this method.
Parses date as an HTTP-date defined by RFC 2616 and converts it to a Time object.
ArgumentError is raised if date is not compliant with RFC 2616 or if the Time class cannot represent specified date.
See httpdate for more information on this format.
require 'time' Time.httpdate("Thu, 06 Oct 2011 02:26:12 GMT") #=> 2011-10-06 02:26:12 UTC
You must require ‘time’ to use this method.
Returns a string which represents the time as RFC 1123 date of HTTP-date defined by RFC 2616:
day-of-week, DD month-name CCYY hh:mm:ss GMT
Note that the result is always UTC (GMT).
require 'time' t = Time.now t.httpdate # => "Thu, 06 Oct 2011 02:26:12 GMT"
You must require ‘time’ to use this method.
Creates a new Time object with the value given by time, the given number of seconds_with_frac, or seconds and microseconds_with_frac since the Epoch. seconds_with_frac and microseconds_with_frac can be an Integer, Float, Rational, or other Numeric. non-portable feature allows the offset to be negative on some systems.
If in argument is given, the result is in that timezone or UTC offset, or if a numeric argument is given, the result is in local time.
Time.at(0) #=> 1969-12-31 18:00:00 -0600 Time.at(Time.at(0)) #=> 1969-12-31 18:00:00 -0600 Time.at(946702800) #=> 1999-12-31 23:00:00 -0600 Time.at(-284061600) #=> 1960-12-31 00:00:00 -0600 Time.at(946684800.2).usec #=> 200000 Time.at(946684800, 123456.789).nsec #=> 123456789 Time.at(946684800, 123456789, :nsec).nsec #=> 123456789
Same as Time::gm, but interprets the values in the local time zone.
Time.local(2000,"jan",1,20,15,1) #=> 2000-01-01 20:15:01 -0600
Converts time to local time (using the local time zone in effect at the creation time of time) modifying the receiver.
If utc_offset is given, it is used instead of the local time.
t = Time.utc(2000, "jan", 1, 20, 15, 1) #=> 2000-01-01 20:15:01 UTC t.utc? #=> true t.localtime #=> 2000-01-01 14:15:01 -0600 t.utc? #=> false t.localtime("+09:00") #=> 2000-01-02 05:15:01 +0900 t.utc? #=> false
If utc_offset is not given and time is local time, just returns the receiver.
Converts time to UTC (GMT), modifying the receiver.
t = Time.now #=> 2007-11-19 08:18:31 -0600 t.gmt? #=> false t.gmtime #=> 2007-11-19 14:18:31 UTC t.gmt? #=> true t = Time.now #=> 2007-11-19 08:18:51 -0600 t.utc? #=> false t.utc #=> 2007-11-19 14:18:51 UTC t.utc? #=> true
Returns a canonical string representation of time.
Time.now.asctime #=> "Wed Apr 9 08:56:03 2003" Time.now.ctime #=> "Wed Apr 9 08:56:03 2003"
Returns a canonical string representation of time.
Time.now.asctime #=> "Wed Apr 9 08:56:03 2003" Time.now.ctime #=> "Wed Apr 9 08:56:03 2003"
Returns the month of the year (1..12) for time.
t = Time.now #=> 2007-11-19 08:27:30 -0600 t.mon #=> 11 t.month #=> 11
Returns true if time represents Thursday.
t = Time.local(1995, 12, 21) #=> 1995-12-21 00:00:00 -0600 t.thursday? #=> true
Returns true if time represents Saturday.
t = Time.local(2006, 6, 10) #=> 2006-06-10 00:00:00 -0500 t.saturday? #=> true
Formats time according to the directives in the given format string.
The directives begin with a percent (%) character. Any text not listed as a directive will be passed through to the output string.
The directive consists of a percent (%) character, zero or more flags, optional minimum field width, optional modifier and a conversion specifier as follows:
%<flags><width><modifier><conversion>
Flags:
- don't pad a numerical output _ use spaces for padding 0 use zeros for padding ^ upcase the result string # change case : use colons for %z
The minimum field width specifies the minimum width.
The modifiers are “E” and “O”. They are ignored.
Format directives:
Date (Year, Month, Day):
%Y - Year with century if provided, will pad result at least 4 digits.
-0001, 0000, 1995, 2009, 14292, etc.
%C - year / 100 (rounded down such as 20 in 2009)
%y - year % 100 (00..99)
%m - Month of the year, zero-padded (01..12)
%_m blank-padded ( 1..12)
%-m no-padded (1..12)
%B - The full month name (``January'')
%^B uppercased (``JANUARY'')
%b - The abbreviated month name (``Jan'')
%^b uppercased (``JAN'')
%h - Equivalent to %b
%d - Day of the month, zero-padded (01..31)
%-d no-padded (1..31)
%e - Day of the month, blank-padded ( 1..31)
%j - Day of the year (001..366)
Time (Hour, Minute, Second, Subsecond):
%H - Hour of the day, 24-hour clock, zero-padded (00..23)
%k - Hour of the day, 24-hour clock, blank-padded ( 0..23)
%I - Hour of the day, 12-hour clock, zero-padded (01..12)
%l - Hour of the day, 12-hour clock, blank-padded ( 1..12)
%P - Meridian indicator, lowercase (``am'' or ``pm'')
%p - Meridian indicator, uppercase (``AM'' or ``PM'')
%M - Minute of the hour (00..59)
%S - Second of the minute (00..60)
%L - Millisecond of the second (000..999)
The digits under millisecond are truncated to not produce 1000.
%N - Fractional seconds digits, default is 9 digits (nanosecond)
%3N millisecond (3 digits)
%6N microsecond (6 digits)
%9N nanosecond (9 digits)
%12N picosecond (12 digits)
%15N femtosecond (15 digits)
%18N attosecond (18 digits)
%21N zeptosecond (21 digits)
%24N yoctosecond (24 digits)
The digits under the specified length are truncated to avoid
carry up.
Time zone:
%z - Time zone as hour and minute offset from UTC (e.g. +0900)
%:z - hour and minute offset from UTC with a colon (e.g. +09:00)
%::z - hour, minute and second offset from UTC (e.g. +09:00:00)
%Z - Abbreviated time zone name or similar information. (OS dependent)
Weekday:
%A - The full weekday name (``Sunday'')
%^A uppercased (``SUNDAY'')
%a - The abbreviated name (``Sun'')
%^a uppercased (``SUN'')
%u - Day of the week (Monday is 1, 1..7)
%w - Day of the week (Sunday is 0, 0..6)
ISO 8601 week-based year and week number:
The first week of YYYY starts with a Monday and includes YYYY-01-04.
The days in the year before the first week are in the last week of
the previous year.
%G - The week-based year
%g - The last 2 digits of the week-based year (00..99)
%V - Week number of the week-based year (01..53)
Week number:
The first week of YYYY that starts with a Sunday or Monday (according to %U
or %W). The days in the year before the first week are in week 0.
%U - Week number of the year. The week starts with Sunday. (00..53)
%W - Week number of the year. The week starts with Monday. (00..53)
Seconds since the Epoch:
%s - Number of seconds since 1970-01-01 00:00:00 UTC.
Literal string:
%n - Newline character (\n)
%t - Tab character (\t)
%% - Literal ``%'' character
Combination:
%c - date and time (%a %b %e %T %Y)
%D - Date (%m/%d/%y)
%F - The ISO 8601 date format (%Y-%m-%d)
%v - VMS date (%e-%^b-%4Y)
%x - Same as %D
%X - Same as %T
%r - 12-hour time (%I:%M:%S %p)
%R - 24-hour time (%H:%M)
%T - 24-hour time (%H:%M:%S)
This method is similar to strftime() function defined in ISO C and POSIX.
While all directives are locale independent since Ruby 1.9, %Z is platform dependent. So, the result may differ even if the same format string is used in other systems such as C.
%z is recommended over %Z. %Z doesn’t identify the timezone. For example, “CST” is used at America/Chicago (-06:00), America/Havana (-05:00), Asia/Harbin (+08:00), Australia/Darwin (+09:30) and Australia/Adelaide (+10:30). Also, %Z is highly dependent on the operating system. For example, it may generate a non ASCII string on Japanese Windows, i.e. the result can be different to “JST”. So the numeric time zone offset, %z, is recommended.
Examples:
t = Time.new(2007,11,19,8,37,48,"-06:00") #=> 2007-11-19 08:37:48 -0600 t.strftime("Printed on %m/%d/%Y") #=> "Printed on 11/19/2007" t.strftime("at %I:%M %p") #=> "at 08:37 AM"
Various ISO 8601 formats:
%Y%m%d => 20071119 Calendar date (basic) %F => 2007-11-19 Calendar date (extended) %Y-%m => 2007-11 Calendar date, reduced accuracy, specific month %Y => 2007 Calendar date, reduced accuracy, specific year %C => 20 Calendar date, reduced accuracy, specific century %Y%j => 2007323 Ordinal date (basic) %Y-%j => 2007-323 Ordinal date (extended) %GW%V%u => 2007W471 Week date (basic) %G-W%V-%u => 2007-W47-1 Week date (extended) %GW%V => 2007W47 Week date, reduced accuracy, specific week (basic) %G-W%V => 2007-W47 Week date, reduced accuracy, specific week (extended) %H%M%S => 083748 Local time (basic) %T => 08:37:48 Local time (extended) %H%M => 0837 Local time, reduced accuracy, specific minute (basic) %H:%M => 08:37 Local time, reduced accuracy, specific minute (extended) %H => 08 Local time, reduced accuracy, specific hour %H%M%S,%L => 083748,000 Local time with decimal fraction, comma as decimal sign (basic) %T,%L => 08:37:48,000 Local time with decimal fraction, comma as decimal sign (extended) %H%M%S.%L => 083748.000 Local time with decimal fraction, full stop as decimal sign (basic) %T.%L => 08:37:48.000 Local time with decimal fraction, full stop as decimal sign (extended) %H%M%S%z => 083748-0600 Local time and the difference from UTC (basic) %T%:z => 08:37:48-06:00 Local time and the difference from UTC (extended) %Y%m%dT%H%M%S%z => 20071119T083748-0600 Date and time of day for calendar date (basic) %FT%T%:z => 2007-11-19T08:37:48-06:00 Date and time of day for calendar date (extended) %Y%jT%H%M%S%z => 2007323T083748-0600 Date and time of day for ordinal date (basic) %Y-%jT%T%:z => 2007-323T08:37:48-06:00 Date and time of day for ordinal date (extended) %GW%V%uT%H%M%S%z => 2007W471T083748-0600 Date and time of day for week date (basic) %G-W%V-%uT%T%:z => 2007-W47-1T08:37:48-06:00 Date and time of day for week date (extended) %Y%m%dT%H%M => 20071119T0837 Calendar date and local time (basic) %FT%R => 2007-11-19T08:37 Calendar date and local time (extended) %Y%jT%H%MZ => 2007323T0837Z Ordinal date and UTC of day (basic) %Y-%jT%RZ => 2007-323T08:37Z Ordinal date and UTC of day (extended) %GW%V%uT%H%M%z => 2007W471T0837-0600 Week date and local time and difference from UTC (basic) %G-W%V-%uT%R%:z => 2007-W47-1T08:37-06:00 Week date and local time and difference from UTC (extended)
Returns the number of entries in the database.
Updates the database with multiple values from the specified object. Takes any object which implements the each_pair method, including Hash and DBM objects.
Returns true if the database contains the specified key, false otherwise.
Returns the number of struct members.
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.length #=> 3
Returns the struct members as an array of symbols:
Customer = Struct.new(:name, :address, :zip) joe = Customer.new("Joe Smith", "123 Maple, Anytown NC", 12345) joe.members #=> [:name, :address, :zip]
Reads and returns a line without echo back. Prints prompt unless it is nil.
You must require ‘io/console’ to use this method.
Returns status information for ios as an object of type File::Stat.
f = File.new("testfile") s = f.stat "%o" % s.mode #=> "100644" s.blksize #=> 4096 s.atime #=> Wed Apr 09 08:53:54 CDT 2003
Immediately writes all buffered data in ios to disk.
If the underlying operating system does not support fdatasync(2), IO#fsync is called instead (which might raise a NotImplementedError).
Reads at most maxlen bytes from the I/O stream. It blocks only if ios has no data immediately available. It doesn’t block if some data available.
If the optional outbuf argument is present, it must reference a String, which will receive the data. The outbuf will contain only the received data after the method call even if it is not empty at the beginning.
It raises EOFError on end of file.
readpartial is designed for streams such as pipe, socket, tty, etc. It blocks only when no data immediately available. This means that it blocks only when following all conditions hold.
the byte buffer in the IO object is empty.
the content of the stream is empty.
the stream is not reached to EOF.
When readpartial blocks, it waits data or EOF on the stream. If some data is reached, readpartial returns with the data. If EOF is reached, readpartial raises EOFError.
When readpartial doesn’t blocks, it returns or raises immediately. If the byte buffer is not empty, it returns the data in the buffer. Otherwise if the stream has some content, it returns the data in the stream. Otherwise if the stream is reached to EOF, it raises EOFError.
r, w = IO.pipe # buffer pipe content w << "abc" # "" "abc". r.readpartial(4096) #=> "abc" "" "" r.readpartial(4096) # blocks because buffer and pipe is empty. r, w = IO.pipe # buffer pipe content w << "abc" # "" "abc" w.close # "" "abc" EOF r.readpartial(4096) #=> "abc" "" EOF r.readpartial(4096) # raises EOFError r, w = IO.pipe # buffer pipe content w << "abc\ndef\n" # "" "abc\ndef\n" r.gets #=> "abc\n" "def\n" "" w << "ghi\n" # "def\n" "ghi\n" r.readpartial(4096) #=> "def\n" "" "ghi\n" r.readpartial(4096) #=> "ghi\n" "" ""
Note that readpartial behaves similar to sysread. The differences are:
If the byte buffer is not empty, read from the byte buffer instead of “sysread for buffered IO (IOError)”.
It doesn’t cause Errno::EWOULDBLOCK and Errno::EINTR. When readpartial meets EWOULDBLOCK and EINTR by read system call, readpartial retry the system call.
The latter means that readpartial is nonblocking-flag insensitive. It blocks on the situation IO#sysread causes Errno::EWOULDBLOCK as if the fd is blocking mode.
Returns true if ios is associated with a terminal device (tty), false otherwise.
File.new("testfile").isatty #=> false File.new("/dev/tty").isatty #=> true