Linux file命令详解程序员

file: 查看文件类型

file常见命令参数

Usage: file [OPTION...] [FILE...] 
Determine type of FILEs. 
 
      --help                 display this help and exit 
  -v, --version              output version information and exit 
  -m, --magic-file LIST      use LIST as a colon-separated list of magic 
                               number files 
  -z, --uncompress           try to look inside compressed files 
  -b, --brief                do not prepend filenames to output lines 
  -c, --checking-printout    print the parsed form of the magic file, use in 
                               conjunction with -m to debug a new magic file 
                               before installing it 
  -e, --exclude TEST         exclude TEST from the list of test to be 
                               performed for file. Valid tests are: 
                               ascii, apptype, compress, elf, soft, tar, tokens, troff 
  -f, --files-from FILE      read the filenames to be examined from FILE 
  -F, --separator STRING     use string as separator instead of `:' 
  -i, --mime                 output MIME type strings (--mime-type and 
                               --mime-encoding) 
      --apple                output the Apple CREATOR/TYPE 
      --mime-type            output the MIME type 
      --mime-encoding        output the MIME encoding 
  -k, --keep-going           don't stop at the first match 
  -L, --dereference          follow symlinks (default) 
  -h, --no-dereference       don't follow symlinks 
  -n, --no-buffer            do not buffer output 
  -N, --no-pad               do not pad output 
  -0, --print0               terminate filenames with ASCII NUL 
  -p, --preserve-date        preserve access times on files 
  -r, --raw                  don't translate unprintable chars to /ooo 
  -s, --special-files        treat special (block/char devices) files as 
                             ordinary ones 
  -C, --compile              compile file specified by -m 
  -d, --debug                print debugging messages

常用的命令展示

file  /var/log/secure*    –>显示是二进制文件

file /var/log/lastlog      –>显示是data文件   –>不能cat –> 只能last命令查看

#!/bin/bash 
#脚本说明 
#压缩案例: sh ./ext.sh en /root/a.zip ./test 压缩类型 压缩后的文件名 要压缩的文件或者目录 
#解压案例: sh ./ext.sh de ./a.zip 压缩类型 解压的文件名 （默认当前目录） 
type=$1 #压缩类型，en表示压缩，de表示解压 
filename=$2 #文件名 
to_filename=$3 #如果是压缩则是选择压缩的文件，解压则是输出的文件路径 
ext="${filename##*.}" #获取到文件名的后缀 
if [ ! $filename ] 
then 
        #没有传入参数 
        echo 'error(100)not file(tar|gz|bz2|zip|rar)' 
        exit 0 
fi 
if [ $type = 'en' ] 
then 
        #压缩至 
        #匹配相应的文件 
        case $ext in 
        'tar') 
                eval "tar cvf $filename $to_filename" 
                ;; 
        'gz') 
                eval "tar zcvf $filename $to_filename" 
                ;; 
        'bz2') 
                eval "tar jcvf $filename $to_filename"  
                ;; 
        'zip') 
                eval "zip $filename $to_filename" 
                ;; 
        *) 
                #不支持该类型 
                echo 'error(101)This type is not supported(tar|gz|bz2|zip)' 
                ;; 
        esac 
else 
        #解压至 
        #匹配相应的文件 
        case $ext in 
        'tar') 
                eval "tar xvf $filename" 
                ;; 
        'gz') 
                eval "tar zxvf $filename" 
                ;; 
        'bz2') 
                eval "tar jxvf $filename" 
                ;; 
        'zip') 
                eval "unzip $filename" 
                ;; 
        *) 
                #不支持该类型 
                echo 'error(101)This type is not supported(tar|gz|bz2|zip)' 
                ;; 
        esac 
fi