unix - Can ext4 detect corrupted file contents? -

can ext4 filesystem detect data corruption of file contents? if yes, enabled default , how can check corrupted data?

i have read ext4 maintains checksums file metadata , journal, unable find information on checksums actual file contents.

for clarity: want know if file has changed since last write operation.

"can ext4 filesystem detect data corruption of file contents?" not in sense expecting. performs journaling, creating boolean {before vs after} copy ensure io completion.

a crc / checksum test modification known state , although crc or checksum may not compare original, not imply file "corrupt" (aka invalid) - - says has been changed. strictly speaking, 1 form of "corruption" alter 'magic number' @ beginning of file, changing %pdf %xyz - - make content unusable program.

"... know if file has changed since last write operation". systems track mtime() uniformly, every write modify mtime() making request impossible.

the way mtime() not reflect last write io media degredation.