管道 | 与重定向 ＞

系列文章目录

1.1 压缩与解压缩命令
2.1 head、tail查看文件
3 grep文本搜索工具
4 管道 | 与重定向 >

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一、管道 |

管道仅能处理经由前面一个指令传出的正确输出信息，也就是standard output的信息，对于standard error信息没有直接处理能力。

然后将standard output作为标准的输入传递给下一个命令。

使用格式：

[命令] | [命令]

例如：

head -n 10 all_viruses_nucleotide_sequences_20171115.fasta | grep '>'
>BHFishC185032_Beihai_conger_calicivirus_6981bp
>BHFishC186477_Beihai_fish_calicivirus_6847bp
>BHFishC187917_Beihai_yellowfin_seabream_calicivirus_6816bp
>BHFishC181798_Beihai_rabbitfish_calicivirus_1_4604bp
>BHFishC188521_Beihai_rabbitfish_calicivirus_2_5721bp

二、重定向 >

使用 > 可以将本应该出现在屏幕的标准输出信息重定向到一个文件中。

使用格式：

[命令] > [命令]

例如：

head -n 10 all_viruses_nucleotide_sequences_20171115.fasta | grep '>' > BHF.txt
>BHFishC185032_Beihai_conger_calicivirus_6981bp
>BHFishC186477_Beihai_fish_calicivirus_6847bp
>BHFishC187917_Beihai_yellowfin_seabream_calicivirus_6816bp
>BHFishC181798_Beihai_rabbitfish_calicivirus_1_4604bp
>BHFishC188521_Beihai_rabbitfish_calicivirus_2_5721bp
tail -n 10 all_viruses_nucleotide_sequences_20171115.fasta | grep '>' > WHW.txt
>WHWGC151314_Chinese_broad-headed_pond_turtle_picornavirus_1_9218bp
>WHWGGF74766_Tortoise_Rafivirus_A_7315bp
>WHWGGF75534_Chinese_broad-headed_pond_turtle_picornavirus_2_7999bp
>WHWGGF64311_Chinese_broad-headed_pond_turtle_hepacivirus_8764bp
>XMTSYG10372_Xiamen_fanray_pesti-like_virus_11039bp
cat WHW.txt BHF.txt > combine.txt
cat combine.txt
>WHWGC151314_Chinese_broad-headed_pond_turtle_picornavirus_1_9218bp
>WHWGGF74766_Tortoise_Rafivirus_A_7315bp
>WHWGGF75534_Chinese_broad-headed_pond_turtle_picornavirus_2_7999bp
>WHWGGF64311_Chinese_broad-headed_pond_turtle_hepacivirus_8764bp
>XMTSYG10372_Xiamen_fanray_pesti-like_virus_11039bp
>BHFishC185032_Beihai_conger_calicivirus_6981bp
>BHFishC186477_Beihai_fish_calicivirus_6847bp
>BHFishC187917_Beihai_yellowfin_seabream_calicivirus_6816bp
>BHFishC181798_Beihai_rabbitfish_calicivirus_1_4604bp
>BHFishC188521_Beihai_rabbitfish_calicivirus_2_5721bp