文件系统和程序的限制关系——ulimit

[root@localhost opt]# ulimit -f 20480
[root@localhost opt]# dd if=/dev/zero of=file bs=1M count=30
File size limit exceeded (core dumped)
[root@localhost opt]# dd if=/dev/zero of=file bs=1M count=15
15+0 records in
15+0 records out
15728640 bytes (16 MB) copied, 0.523044 s, 30.1 MB/s
[root@localhost opt]#