为何在系统中找不到使用yum_yum命令时所需的具体参数选项？

没有yum 命令参数的情况：
当你在Linux系统中输入yum 命令而没有提供任何参数时，系统会默认显示yum 命令的帮助信息，以下是一个典型的帮助信息输出：

Usage: yum [options] [command] [package …]

Options:

h, help display this help and exit

V, version display the version of yum and exit

q, quiet quiet command output

y, assumeyes assume "yes" in all yes/no prompts

assumeno assume "no" in all yes/no prompts

c, config <config> specify a configuration file

cacheonly only use cache

enablerepo=<repo> enable repository

disablerepo=<repo> disable repository

noplugins do not load plugins

nogpgcheck do not perform GPG checks on packages

repoquery=<repo> query a repository

repoid=<repo> specify a repository id

disablerepo=<repo> disable repository ( Overrides enablerepo )

enablerepo=<repo> enable repository ( Overrides disablerepo )

erroronfail stop on the first error seen

disableplugin=<plugin> disable a plugin

enablerepo=<repo> enable repository

disablegroupupdate disable updating of groups

skipbroken skip packages with unresolvable dependencies

showduplicates show all available versions of packages

obsoletes show the packages that would be replaced by the best version

best show only the best version of each package

allmatches show all matches when searching, not just the best

groupinstall=<group> install a package group

groupupdate update a package group

groupremove=<group> remove a package group

grouplist list a package group

dumpcache dump the cache to stdout

cleancache clean yum cache

clean metadata clean yum metadata

destdir=<dir> specify an install directory

installroot=<dir> specify a root directory to install to

obsoletes show the packages that would be replaced by the best version

best show only the best version of each package

debug enable debug mode

syslog log to syslog

quiet quiet command output

verbose verbose command output

bugreport prepare a bug report by gathering debugging information

bugzilla prepare a bug report by gathering debugging information

bugzillaemail=<email> send bug report to bugzilla using the specified email

bugzillabugzilla=<bugzilla> specify bugzilla server to send bug report

bugzillaproduct=<product> specify bugzilla product to send bug report

bugzillacomponent=<component> specify bugzilla component to send bug report

bugzillacc=<cc> specify bugzilla cc to send bug report

bugzillabts=<bts> specify bugzilla bts to send bug report

bugzillaccproduct=<cc_product> specify bugzilla cc product to send bug report

bugzillacccomponent=<cc_component> specify bugzilla cc component to send bug report

bugzillaccbts=<cc_bts> specify bugzilla cc bts to send bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<file> write bug report to a file

bugzillacomment=<comment> add a comment to the bug report

bugzillabtscomment=<bts_comment> add a comment to the bug report

bugzillacccomment=<cc_comment> add a comment to the bug report

bugzillaccproductcomment=<cc_product_comment> add a comment to the bug report

bugzillacccomponentcomment=<cc_component_comment> add a comment to the bug report

bugzillaccbtscomment=<cc_bts_comment> add a comment to the bug report

bugzillahelp display bugzilla options and exit

bugzillaversion display bugzilla version and exit

bugzillaoutput=<