df (disk free) : 디스크 용량확인 df --help 사용법: df [옵션]... [파일]... Show information about the file system on which each FILE resides, or all file systems by default. 긴 옵션에서 꼭 필요한 인수는 짧은 옵션에도 꼭 필요합니다. -a, --all include dummy file systems -B, --block-size=SIZE use SIZE-byte blocks --total produce a grand total -h, --human-readable print sizes in human readable format (e.g., 1K 234M 2G) -H, --si likewise,..