常用shell脚本

如何用脚本实现分割文件

#!/bin/bash

if [ $# -ne 2 ]; then

echo 'Usage: split file size(in bytes)'

exit

fi

file=$1

size=$2

if [ ! -f $file ]; then

echo "$file doesn't exist"

exit

fi

#TODO: test if $size is a valid integer

filesize=`/bin/ls -l $file | awk '{print $5}'`

echo filesize: $filesize

let pieces=$filesize/$size

let remain=$filesize-$pieces*$size

if [ $remain -gt 0 ]; then

let pieces=$pieces+1

fi

echo pieces: $pieces

i=0

while [ $i -lt $pieces ];

do

echo split: $file.$i:

dd if=$file of=$file.$i bs=$size count=1 skip=$i let i=$i+1

done

echo "#!/bin/bash" >; merge

echo "i=0" >;>; merge

echo "while [ $i -lt $pieces ];" >;>; merge

echo "do" >;>; merge

echo " echo merge: $file.$i" >;>; merge

echo " if [ ! -f $file.$i ]; then" >;>; merge

echo " echo merge: $file.$i missed" >;>; merge

echo " exit" >;>; merge

echo " fi" >;>; merge

echo " dd if=$file.$i of=$file.merged bs=$size count=1 seek=$i" >;>; merge

echo " let i=$i+1" >;>; merge

echo "done" >;>; merge

chmod u+x merge'

如何查找日期为某一天的文件

#!/bin/sh

# The right of usage, distribution and modification is here by granted by the author.

# The author deny any responsibilities and liabilities related to the code. #

OK=0

A=`find $1 -print`

if expr $3 == 1 >;/dev/null ; then M=Jan ; OK=1 ; fi

if expr $3 == 2 >;/dev/null ; then M=Feb ; OK=1 ; fi

if expr $3 == 3 >;/dev/null ; then M=Mar ; OK=1 ; fi

if expr $3 == 4 >;/dev/null ; then M=Apr ; OK=1 ; fi

if expr $3 == 5 >;/dev/null ; then M=May ; OK=1 ; fi

if expr $3 == 6 >;/dev/null ; then M=Jun ; OK=1 ; fi

if expr $3 == 7 >;/dev/null ; then M=Jul ; OK=1 ; fi

if expr $3 == 8 >;/dev/null ; then M=Aug ; OK=1 ; fi

if expr $3 == 9 >;/dev/null ; then M=Sep ; OK=1 ; fi

if expr $3 == 10 >;/dev/null ; then M=Oct ; OK=1 ; fi

if expr $3 == 11 >;/dev/null ; then M=Nov ; OK=1 ; fi

if expr $3 == 12 >;/dev/null ; then M=Dec ; OK=1 ; fi

if expr $3 == 1 >;/dev/null ; then M=Jan ; OK=1 ; fi

if expr $OK == 1 >; /dev/null ; then

ls -l --full-time $A 2>;/dev/null | grep "$M $4" | grep $2 ;

else

echo Usage: $0 path Year Month Day;

echo Example: $0 ~ 1998 6 30;

fi

如何计算当前目录下的文件数和目录数

# ls -l * |grep "^-"|wc -l ---- to count files

# ls -l * |grep "^d"|wc -l ----- to count dir

如何只列子目录？

ls -F | grep /$ 或者 alias sub = "ls -F | grep /$"(linux)

ls -l | grep "^d" 或者 ls -lL | grep "^d" (Solaris)

如何实现取出文件中特定的行内容

如果你只想看文件的前5行，可以使用head命令，

如： head -5 /etc/passwd

如果你想查看文件的后10行，可以使用tail命令，