Sync

lastmod 2026-02-06created 2026-02-063 edits

Forces pending write operations left in memory buffers to be flushed to disk. Linux buffers disk writes for performance, and calling sync waits until all data in the buffers has actually been written to the disk (USB).

Usage

sudo sync
# USB를 물리적으로 뽑기 전에 반드시 실행
# 안 하면 데이터가 불완전하게 기록되어 부팅 실패 또는 파일 손상 발생 가능

Using the oflag=sync option in dd works on the same principle, guaranteeing synchronization for every block write.

See also

• fdisk
• mkfs
• dd
• wipefs
• sgdisk
• partprobe
• sync