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我编写了一个琐碎的bash脚本，该脚本从文件或STDIN中转储随机行：
#!/bin/bash
if [ $# -ne 1 ]
then
echo \"Syntax: $0 FILE (or \\\'-\\\' for STDIN)\"
echo $0 - display a random line from FILE
exit 1
fi
RAND=`cat /proc/sys/kernel/random/uuid | cut -c1-4 | od -d | head -1 | cut -d\' \' -f2`
if [ $1 != \"-\" ]
then
LINES=`cat \"$1\" | wc -l`
LINE=`expr $RAND % $LINES + 1`
head -$LINE $1 | tail -1
else
piped=`cat -`
LINES=`echo \"$piped\" | wc -l`
LINE=`expr $RAND % $LINES + 1`
echo \"$piped\" | head -$LINE | tail -1
fi
echo \"foo\\nbar\\nbaz\" | randline
echo \"foo\\n\\bar\\nbaz\" | randline -
#!/bin/bash
if [ \"$( tty )\" == \'not a tty\' ]
then
STDIN_DATA_PRESENT=1
else
STDIN_DATA_PRESENT=0
fi
if [[ $# -ne 1 && $STDIN_DATA_PRESENT -eq 0 ]]
then
echo \"Syntax: $0 [FILE (or \\\'-\\\' for STDIN)]\"
echo $0 - display a random line from FILE
echo -e \"\\nWill also process piped STDIN if no arguments are given.\"
exit 1
fi
RAND=`cat /proc/sys/kernel/random/uuid | cut -c1-4 | od -d | head -1 | cut -d\' \' -f2`
if [[ $1 && $1 != \"-\" ]]
then
LINES=`cat \"$1\" | wc -l`
LINE=`expr $RAND % $LINES + 1`
head -$LINE $1 | tail -1
else
piped=`cat -`
LINES=`echo \"$piped\" | wc -l`
LINE=`expr $RAND % $LINES + 1`
echo \"$piped\" | head -$LINE | tail -1
fi
没有找到相关结果
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链眷克袒姜
awk \'BEGIN{srand();}{printf \"%04d %s\\n\", int(rand()*10000), $0}\' < $FILENAME | sort | cut -f2- -d\' \' | head -1