Linux 使用命令 1

fold :

Usage: fold [OPTION]... [FILE]...
Wrap input lines in each FILE (standard input by default), writing to
standard output.

Mandatory arguments to long options are mandatory for short options too.
　　-b, --bytes count bytes rather than columns
　　-c, --characters count characters rather than columns
　　-s, --spaces break at spaces
　　-w, --width=WIDTH use WIDTH columns instead of 80
　　--help display this help and exit
　　--version output version information and exit

example:

[heshuai@login01 data_for_others]$ cat yq |fold -w 50
>q::chr3:171337789-171338789()
GATTCTGCAATTTTCACGAAGTCCATTTAATTGCTCTGTACCTCTGATTC
TTCACAGATAAAAATAGTTTAGTTcacaaagagatgataaatgcttgaag
tgataggtactgcaattgccctgatgtgattgttatacattgtatgactg
tatcaaaacatcgtatgtaccccatgaatatatacacctattctgtacct
ataacaattTCAACAACTGGGTTAGAAAGGATGTAAGAGAAGAGGATGGC
TTCAGAAATGTTTTAGTTATGGTGTTACTGTCTGTTTCAAATGCAAAGGA
TGCTTAGGAGGAATAGCAGCAAACATTTTTGCATGGGGTAAGTCAACTGG
CAAGGAATACAATTATAGACCATATACTGTACTTACCAATAATAACAGTG
TTATCATCAGCAATTAACAACTTGCTGTGGACATAGATAAGCTCAGTTAC
TAGGTTTCCTTCGAGCTCTGCATGTGTTCTAAGACCACAGAATGATATGT
AATTTATCCACTGATTACCAACTGCaaatttaaaaagaaattattaaaat
taatatGACCAAGCTCAATAAACGTACATTAAATCTTATTGTTTCTCAAA
ACATACTACTTAGACTGTTCAGAATAGATTGTATATTATATGTATATGTT
TTCTATTTCAGAATTCATCCAGGATTTATTTTTGATATCTGAATTTCATA
TTGTCAGTCTGAATGGctttctctctctctctctctctctctctatatat
atatatatatatatatatattatatatatTTTTTTTTTAATTGAAGTGTT
TTCTGTCTTCCCTTTGCTAAGGCAATCCAAAAAGCTATTCATATATGAAC
ATTTTATTTTAATGATTTGATGAGTTAACTACTGAAGAGTGATGGTTAAA
ACTGAGCTGGAATAGATTAACCAAGACTTCAGTGTGACATTTGCTTCTAT
CCTGCTTGACACTTGCTGCAGTTTGAATCAGATGCAAGGTGTGTGCCAAA

print the sequence limit the nucleotides to 50 per line.