2-4CLI DisplayBy filtering the output information, you can find the wanted information effectively. If there is a lot ofinformation to be displayed, the system displays the information in multiple screens. When theinformation is displayed in multiple screens, you can also filter the output information to pick up thewanted information.Filtering the output informationThe device provides the function to filter the output information. You can specify a regular expression(that is, the output rule) to search information you need.You can use one of the following two ways to filter the output information:z Input the keyword begin, exclude, or include as well as the regular expression at the commandline to filter the output information.z Input slash (/), minus (-), or plus (+) as well as the regular expression to filter the rest outputinformation. Slash (/) is equal to the keyword begin, minus (-) is equal to the keyword exclude, andplus (+) is equal to the keyword include.Keywords begin, exclude, and include have the following meanings:z begin: Displays the line that matches the regular expression and all the subsequent lines.z exclude: Displays the lines that do not match the regular expression.z include: Displays only the lines that match the regular expression.The regular expression is a string of 1 to 256 characters, case sensitive. It also supports specialcharacters as shown in Table 2-2.Table 2-2 Special characters in a regular expressionCharacter Meaning Remarks^string Starting sign, string appears only at thebeginning of a line.For example, regular expression “^user”only matches a string beginning with“user”, not “Auser”.string$ Ending sign, string appears only at theend of a line.For example, regular expression "user$”only matches a string ending with “user”,not “userA”..Full stop, a wildcard used in place of anycharacter, including single character,special character and blank.For example, “.l” can match “vlan” or“mpls”.*Asterisk, used to match a character orcharacter group before it zero or multipletimes.For example, “zo*” can match “z” and“zoo”; (zo)* can match “zo” and “zozo”.+Addition, used to match a character orcharacter group one or multiple timesbefore itFor example, “zo+” can match “zo” and“zoo”, but not “z”.| Vertical bar, used to match the wholestring on the left or right of itFor example, “def|int” can only match acharacter string containing “def” or “int”._Underline. If it is at the beginning or theend of a regular expression, it equals ^ or$; in other cases, it equals comma,space, round bracket, or curly bracket.For example, “a_b” can match “a b” or“a(b”; “_ab” can only match a linestarting with “ab”; “ab_” can only match aline ending with “ab”.
