date

Usage: date [OPTION]… [+FORMAT] or: date [-u|–utc|–universal] [MMDDhhmm.ss Display the current time in the given FORMAT, or set the system date. -d, –dateSTRING display time described by STRING, not `now' -f, –fileDATEFILE like –date once for each line of DATEFILE -r, –referenceFILE display the last modification time of FILE -R, –rfc-2822 output date and time in RFC 2822 format. Example: Mon, 07 Aug 2006 12:34:56 -0600 –rfc-3339TIMESPEC output date and time in RFC 3339 format. TIMESPEC`date', `seconds', or `ns' for date and time to the indicated precision. Date and time components are separated by a single space: 2006-08-07 12:34:56-06:00 -s, –setSTRING set time described by STRING -u, –utc, –universal print or set Coordinated Universal Time –help display this help and exit –version output version information and exit FORMAT controls the output. The only valid option for the second form specifies Coordinated Universal Time. Interpreted sequences are: %% a literal % %a locale's abbreviated weekday name (e.g., Sun) %A locale's full weekday name (e.g., Sunday) %b locale's abbreviated month name (e.g., Jan) %B locale's full month name (e.g., January) %c locale's date and time (e.g., Thu Mar 3 23:05:25 2005) %C century; like %Y, except omit last two digits (e.g., 21) %d day of month (e.g, 01) %D date; same as %m/%d/%y %e day of month, space padded; same as %_d %F full date; same as %Y-%m-%d %g last two digits of year of ISO week number (see %G) %G year of ISO week number (see %V); normally useful only with %V %h same as %b %H hour (00..23) %I hour (01..12) %j day of year (001..366) %k hour ( 0..23) %l hour ( 1..12) %m month (01..12) %M minute (00..59) %n a newline %N nanoseconds (000000000..999999999) %p locale's equivalent of either AM or PM; blank if not known %P like %p, but lower case %r locale's 12-hour clock time (e.g., 11:11:04 PM) %R 24-hour hour and minute; same as %H:%M %s seconds since 1970-01-01 00:00:00 UTC %S second (00..60) %t a tab %T time; same as %H:%M:%S %u day of week (1..7); 1 is Monday %U week number of year, with Sunday as first day of week (00..53) %V ISO week number, with Monday as first day of week (01..53) %w day of week (0..6); 0 is Sunday %W week number of year, with Monday as first day of week (00..53) %x locale's date representation (e.g., 12/31/99) %X locale's time representation (e.g., 23:13:48) %y last two digits of year (00..99) %Y year %z +hhmm numeric timezone (e.g., -0400) %:z +hh:mm numeric timezone (e.g., -04:00) %::z +hh:mm:ss numeric time zone (e.g., -04:00:00) %:::z numeric time zone with : to necessary precision (e.g., -04, +05:30) %Z alphabetic time zone abbreviation (e.g., EDT) By default, date pads numeric fields with zeroes. The following optional flags may follow `%': - (hyphen) do not pad the field (underscore) pad with spaces 0 (zero) pad with zeros ^ use upper case if possible # use opposite case if possible After any flags comes an optional field width, as a decimal number; then an optional modifier, which is either E to use the locale's alternate representations if available, or O to use the locale's alternate numeric symbols if available. Report bugs to <bug-coreutils@gnu.org>. ===== How To Get Yesterday's Date using BASH Shell ===== The new short way: <file> $ date -d '1 day ago' +'%Y/%m/%d' 2012/05/18 </file> Or the longer way: Yesterday in epoch seconds <file> $ yesterday''$¹⁾ </file> Get default formatted yesterday's date <file> $ date -d “1970-01-01 $yesterday sec” Thu May 18 01:27:32 MST 2012 </file> Same thing in YY-MM-DD <file> $ date -d “1970-01-01 $yesterday sec” +“%Y-%m-%d” 2012-05-18 </file> – Main.FredPettis - 2012-05-19

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`date +'%s'` - 86400