{"id":105,"date":"2009-07-31T13:43:30","date_gmt":"2009-07-31T13:43:30","guid":{"rendered":"http:\/\/kumouse.aafox.com\/?p=105"},"modified":"2009-07-31T13:43:30","modified_gmt":"2009-07-31T13:43:30","slug":"bash%e4%b8%ad%e7%9a%84%e5%ad%97%e7%ac%a6%e4%b8%b2%e5%a4%84%e7%90%86","status":"publish","type":"post","link":"https:\/\/www.kumouse.com\/?p=105","title":{"rendered":"bash\u4e2d\u7684\u5b57\u7b26\u4e32\u5904\u7406"},"content":{"rendered":"

bash\u4e2d\u7684\u5b57\u7b26\u4e32\u5904\u7406
  1 \u5f97\u5230\u5b57\u7b26\u4e32\u957f\u5ea6
    [root@redhat test]# s=abcdef
    [root@redhat test]# expr length $s
    6
    [root@redhat test]# echo ${#s}
    6
    [root@redhat test]# expr "$s" : ".*"
    6<\/p>\n

  2 \u67e5\u627e\u5b50\u4e32
    [root@redhat test]# expr index $s a
    1
    [root@redhat test]# expr index $s b
    2
    [root@redhat test]# expr index $s c
    3
    [root@redhat test]# expr index $s d
    4
    [root@redhat test]# expr index $s e
    5
    [root@redhat test]# expr index $s f
    6
    [root@redhat test]# expr index $s g
    0<\/p>\n

  3 \u5f97\u5230\u5b50\u5b57\u7b26\u4e32
    \u8bed\u6cd51\uff1aexpr substr startpos length \u7b2c\u4e00\u4e2a\u5b57\u7b26\u5e8f\u53f7\u4e3a1
    [root@redhat test]# expr substr $s 1 3
    abc
    [root@redhat test]# expr substr $s 1 11
    abcdef
    [root@redhat test]# expr substr $s 3 4
    cdef
    [root@redhat test]# expr substr $s 3 1
    c
    [root@redhat test]# m=1
    [root@redhat test]# j=2
    [root@redhat test]# expr substr $s $m $j<\/p>\n

    \u8bed\u6cd52\uff1a${x:pos:length} \u7b2c\u4e00\u4e2a\u5b57\u7b26\u7684\u5e8f\u53f7\u4e3a0
    [root@redhat test]# expr ${s:0:1}
    a
    [root@redhat test]# expr ${s:2:2}
    cd
    [root@redhat test]# expr ${s:2:11}
    cdef
    [root@redhat test]# m=1
    [root@redhat test]# j=2
    [root@redhat test]# expr ${s:$m:$j}
    bc<\/p>\n

  4 \u5339\u914d\u6b63\u5219\u8868\u8fbe\u5f0f
    [root@redhat test]# expr match $s "ab"
    2
    [root@redhat test]# expr match $s "abc"
    3
    [root@redhat test]# expr match $s "bc"
    0<\/p>\n

  5 \u4fee\u6539\u5b57\u7b26\u4e32\u6390\u5934\u53bb\u5c3e
    #  \u53bb\u9664\u6700\u5c0f\u5339\u914d\u524d\u7f00
    ##  \u53bb\u9664\u6700\u5927\u5339\u914d\u524d\u7f00
    %  \u53bb\u9664\u6700\u5c0f\u5339\u914d\u540e\u7f00
    %%  \u53bb\u9664\u6700\u5927\u5339\u914d\u540e\u7f00
    [root@redhat test]# x=cccdddcccpicxxyyyxxx
    [root@redhat test]# echo ${x%x*x}
    cccdddcccpicxxyyyx
    [root@redhat test]# echo ${x%%x*x}
    cccdddcccpic
    [root@redhat test]# echo ${x#c?c}
    dddcccpicxxyyyxxx
    [root@redhat test]# echo ${x#c*c}
    cdddcccpicxxyyyxxx
    [root@redhat test]# echo ${x#c*c}
    cdddcccpicxxyyyxxx
    [root@redhat test]# echo ${x##c*c}
    xxyyyxxx
    \u8fd9\u91cc\u6b63\u5219\u7528\u7684\u7279\u6b8a\u7b26\u53f7\u662f? * \u5e76\u975e . *<\/p>\n

  6 \u5b57\u7b26\u4e32\u66ff\u6362
    [root@redhat test]# x=efefefef
    [root@redhat test]# echo ${x\/e\/f}
    ffefefef
    [root@redhat test]# echo ${x\/\/e\/f}
    ffffffff
    [root@redhat test]# x=efefacacefacefcb
    [root@redhat test]# echo ${x\/\/ef\/f}
    ffacacfacfcb
    [root@redhat test]# echo ${x\/ef\/f}
    fefacacefacefcb
    [root@redhat test]# echo ${x\/e??\/f}
    ffacacefacefcb
    [root@redhat test]# echo ${x\/\/e??\/f}
    ffacacfcfb
    [root@redhat test]# echo ${x\/f*\/z}
    ez
    \u8fd9\u91cc\u6b63\u5219\u7528\u7684\u7279\u6b8a\u7b26\u53f7\u662f? * , \u4e0d\u53ef\u4ee5\u4f7f\u7528 regexp<\/p>\n","protected":false},"excerpt":{"rendered":"

bash\u4e2d\u7684\u5b57\u7b26\u4e32\u5904\u7406  1 \u5f97\u5230\u5b57\u7b26\u4e32\u957f\u5ea6   &nbsp […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-105","post","type-post","status-publish","format-standard","hentry","category-linux"],"_links":{"self":[{"href":"https:\/\/www.kumouse.com\/index.php?rest_route=\/wp\/v2\/posts\/105","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.kumouse.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kumouse.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kumouse.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kumouse.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=105"}],"version-history":[{"count":0,"href":"https:\/\/www.kumouse.com\/index.php?rest_route=\/wp\/v2\/posts\/105\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.kumouse.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=105"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kumouse.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=105"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kumouse.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=105"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}