bash-4.2$ mknod /var/log/pipe p
mknod :‘/var/log/pipe’: permission denied
bash-4.2$ mknod --help
usage : mknod [ option ] . name type [ major minor ]
createthespecialfilenameofthegiventype。
mandatoryargumentstolongoptionsaremandatoryforshortoptionstoo。
-m，--mode=modesetfilepermissionbitstomode，not a=rw - umask
- zsettheselinuxsecuritycontexttodefaulttype
context [=CTX ] like-z，orifctxisspecifiedthensettheselinux
or SMACK security context to CTX
helpdisplaythishelpandexit
versionoutputversioninformationandexit
bothmajorandminormustbespecifiedwhentypeisb，c，or u，and they
mustbeomittedwhentypeisp.ifmajororminorbeginswith0x or0x，
it is interpreted as hexadecimal； otherwise，if it begins with 0，as octal；
otherwise，as decimal. TYPE may be:
bcreateablock(buffered )特殊文件
c，ucreateacharacter(unbuffered ) special file
p create a FIFO
note : yourshellmayhaveitsownversionofmknod，which usually supersedes
theversiondescribedhere.pleaserefertoyourshell’sdocumentation
fordetailsabouttheoptionsitsupports。
reportmknodtranslationbugsto http://translation project.org/team /
For complete documentation，run : info coreutils‘mknod invocation’