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      1 #!/bin/sh
      2 # Get modification time of a file or directory and pretty-print it.
      3 
      4 scriptversion=2010-08-21.06; # UTC
      5 
      6 # Copyright (C) 1995-2013 Free Software Foundation, Inc.
      7 # written by Ulrich Drepper <drepper (at] gnu.ai.mit.edu>, June 1995
      8 #
      9 # This program is free software; you can redistribute it and/or modify
     10 # it under the terms of the GNU General Public License as published by
     11 # the Free Software Foundation; either version 2, or (at your option)
     12 # any later version.
     13 #
     14 # This program is distributed in the hope that it will be useful,
     15 # but WITHOUT ANY WARRANTY; without even the implied warranty of
     16 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     17 # GNU General Public License for more details.
     18 #
     19 # You should have received a copy of the GNU General Public License
     20 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
     21 
     22 # As a special exception to the GNU General Public License, if you
     23 # distribute this file as part of a program that contains a
     24 # configuration script generated by Autoconf, you may include it under
     25 # the same distribution terms that you use for the rest of that program.
     26 
     27 # This file is maintained in Automake, please report
     28 # bugs to <bug-automake (at] gnu.org> or send patches to
     29 # <automake-patches (at] gnu.org>.
     30 
     31 if test -n "${ZSH_VERSION+set}" && (emulate sh) >/dev/null 2>&1; then
     32   emulate sh
     33   NULLCMD=:
     34   # Pre-4.2 versions of Zsh do word splitting on ${1+"$@"}, which
     35   # is contrary to our usage.  Disable this feature.
     36   alias -g '${1+"$@"}'='"$@"'
     37   setopt NO_GLOB_SUBST
     38 fi
     39 
     40 case $1 in
     41   '')
     42      echo "$0: No file.  Try '$0 --help' for more information." 1>&2
     43      exit 1;
     44      ;;
     45   -h | --h*)
     46     cat <<\EOF
     47 Usage: mdate-sh [--help] [--version] FILE
     48 
     49 Pretty-print the modification day of FILE, in the format:
     50 1 January 1970
     51 
     52 Report bugs to <bug-automake@gnu.org>.
     53 EOF
     54     exit $?
     55     ;;
     56   -v | --v*)
     57     echo "mdate-sh $scriptversion"
     58     exit $?
     59     ;;
     60 esac
     61 
     62 error ()
     63 {
     64   echo "$0: $1" >&2
     65   exit 1
     66 }
     67 
     68 
     69 # Prevent date giving response in another language.
     70 LANG=C
     71 export LANG
     72 LC_ALL=C
     73 export LC_ALL
     74 LC_TIME=C
     75 export LC_TIME
     76 
     77 # GNU ls changes its time format in response to the TIME_STYLE
     78 # variable.  Since we cannot assume 'unset' works, revert this
     79 # variable to its documented default.
     80 if test "${TIME_STYLE+set}" = set; then
     81   TIME_STYLE=posix-long-iso
     82   export TIME_STYLE
     83 fi
     84 
     85 save_arg1=$1
     86 
     87 # Find out how to get the extended ls output of a file or directory.
     88 if ls -L /dev/null 1>/dev/null 2>&1; then
     89   ls_command='ls -L -l -d'
     90 else
     91   ls_command='ls -l -d'
     92 fi
     93 # Avoid user/group names that might have spaces, when possible.
     94 if ls -n /dev/null 1>/dev/null 2>&1; then
     95   ls_command="$ls_command -n"
     96 fi
     97 
     98 # A 'ls -l' line looks as follows on OS/2.
     99 #  drwxrwx---        0 Aug 11  2001 foo
    100 # This differs from Unix, which adds ownership information.
    101 #  drwxrwx---   2 root  root      4096 Aug 11  2001 foo
    102 #
    103 # To find the date, we split the line on spaces and iterate on words
    104 # until we find a month.  This cannot work with files whose owner is a
    105 # user named "Jan", or "Feb", etc.  However, it's unlikely that '/'
    106 # will be owned by a user whose name is a month.  So we first look at
    107 # the extended ls output of the root directory to decide how many
    108 # words should be skipped to get the date.
    109 
    110 # On HPUX /bin/sh, "set" interprets "-rw-r--r--" as options, so the "x" below.
    111 set x`$ls_command /`
    112 
    113 # Find which argument is the month.
    114 month=
    115 command=
    116 until test $month
    117 do
    118   test $# -gt 0 || error "failed parsing '$ls_command /' output"
    119   shift
    120   # Add another shift to the command.
    121   command="$command shift;"
    122   case $1 in
    123     Jan) month=January; nummonth=1;;
    124     Feb) month=February; nummonth=2;;
    125     Mar) month=March; nummonth=3;;
    126     Apr) month=April; nummonth=4;;
    127     May) month=May; nummonth=5;;
    128     Jun) month=June; nummonth=6;;
    129     Jul) month=July; nummonth=7;;
    130     Aug) month=August; nummonth=8;;
    131     Sep) month=September; nummonth=9;;
    132     Oct) month=October; nummonth=10;;
    133     Nov) month=November; nummonth=11;;
    134     Dec) month=December; nummonth=12;;
    135   esac
    136 done
    137 
    138 test -n "$month" || error "failed parsing '$ls_command /' output"
    139 
    140 # Get the extended ls output of the file or directory.
    141 set dummy x`eval "$ls_command \"\\\$save_arg1\""`
    142 
    143 # Remove all preceding arguments
    144 eval $command
    145 
    146 # Because of the dummy argument above, month is in $2.
    147 #
    148 # On a POSIX system, we should have
    149 #
    150 # $# = 5
    151 # $1 = file size
    152 # $2 = month
    153 # $3 = day
    154 # $4 = year or time
    155 # $5 = filename
    156 #
    157 # On Darwin 7.7.0 and 7.6.0, we have
    158 #
    159 # $# = 4
    160 # $1 = day
    161 # $2 = month
    162 # $3 = year or time
    163 # $4 = filename
    164 
    165 # Get the month.
    166 case $2 in
    167   Jan) month=January; nummonth=1;;
    168   Feb) month=February; nummonth=2;;
    169   Mar) month=March; nummonth=3;;
    170   Apr) month=April; nummonth=4;;
    171   May) month=May; nummonth=5;;
    172   Jun) month=June; nummonth=6;;
    173   Jul) month=July; nummonth=7;;
    174   Aug) month=August; nummonth=8;;
    175   Sep) month=September; nummonth=9;;
    176   Oct) month=October; nummonth=10;;
    177   Nov) month=November; nummonth=11;;
    178   Dec) month=December; nummonth=12;;
    179 esac
    180 
    181 case $3 in
    182   ???*) day=$1;;
    183   *) day=$3; shift;;
    184 esac
    185 
    186 # Here we have to deal with the problem that the ls output gives either
    187 # the time of day or the year.
    188 case $3 in
    189   *:*) set `date`; eval year=\$$#
    190        case $2 in
    191 	 Jan) nummonthtod=1;;
    192 	 Feb) nummonthtod=2;;
    193 	 Mar) nummonthtod=3;;
    194 	 Apr) nummonthtod=4;;
    195 	 May) nummonthtod=5;;
    196 	 Jun) nummonthtod=6;;
    197 	 Jul) nummonthtod=7;;
    198 	 Aug) nummonthtod=8;;
    199 	 Sep) nummonthtod=9;;
    200 	 Oct) nummonthtod=10;;
    201 	 Nov) nummonthtod=11;;
    202 	 Dec) nummonthtod=12;;
    203        esac
    204        # For the first six month of the year the time notation can also
    205        # be used for files modified in the last year.
    206        if (expr $nummonth \> $nummonthtod) > /dev/null;
    207        then
    208 	 year=`expr $year - 1`
    209        fi;;
    210   *) year=$3;;
    211 esac
    212 
    213 # The result.
    214 echo $day $month $year
    215 
    216 # Local Variables:
    217 # mode: shell-script
    218 # sh-indentation: 2
    219 # eval: (add-hook 'write-file-hooks 'time-stamp)
    220 # time-stamp-start: "scriptversion="
    221 # time-stamp-format: "%:y-%02m-%02d.%02H"
    222 # time-stamp-time-zone: "UTC"
    223 # time-stamp-end: "; # UTC"
    224 # End:
    225