### Definition of the POSIX C Locale

The POSIX definition of the C locale is described below, with the IBM extensions LC_SYNTAX and LC_TOD showing their default values.

    #############
    LC_CTYPE
    #############
    # "alpha" is by default "upper" and "lower"
    # "alnum" is by definition "alpha" and "digit"
    # "print" is by default "alnum", "punct" and <space> character
    # "graph" is by default "alnum" and "punct"

    upper   <A>;<B>;<C>;<D>;<E>;<F>;<G>;<H>;<I>;<J>;<K>;<L>;<M>;\
            <N>;<O>;<P>;<Q>;<R>;<S>;<T>;<U>;<V>;<W>;<X>;<Y>;<Z>

    lower   <a>;<b>;<c>;<d>;<e>;<f>;<g>;<h>;<i>;<j>;<k>;<l>;<m>;\
            <n>;<o>;<p>;<q>;<r>;<s>;<t>;<u>;<v>;<w>;<x>;<y>;<z>

    digit   <zero>;<one>;<two>;<three>;<four>;\
            <five>;<six>;<seven>;<eight>;<nine>

    space   <tab>;<newline>;<vertical-tab>;<form-feed>;\
            <carriage-return>;<space>

    cntrl   <alert>;<backspace>;<tab>;<newline>;<vertical-tab>;\
            <form-feed>;<carriage-return>;\
            <NUL>;<SOH>;<STX>;<ETX>;<EOT>;<ENQ>;<ACK>;<SO>;\
            <SI>;<DLE>;<DC1>;<DC2>;<DC3>;<DC4>;<NAK>;<SYN>;\
            <ETB>;<CAN>;<EM>;<SUB>;<ESC>;<IS4>;<IS3>;<IS2>;\
            <IS1>;<DEL>

    punct   <exclamation-mark>;<quotation-mark>;<number-sign>;\
            <dollar-sign>;<percent-sign>;<ampersand>;<apostrophe>;\
            <left-parenthesis>;<right-parenthesis>;<asterisk>;\
            <plus-sign>;<comma>;<hyphen>;<period>;<slash>;\
            <colon>;<semicolon>;<less-than-sign>;<equals-sign>;\
            <greater-than-sign>;<question-mark>;<commercial-at>;\
            <left-square-bracket>;<backslash>;<right-square-bracket>;\
            <circumflex>;<underscore>;<grave-accent>;\
            <left-curly-bracket>;<vertical-line>;<right-curly-bracket>;<tilde>

    xdigit  <zero>;<one>;<two>;<three>;<four>;\
            <five>;<six>;<seven>;<eight>;<nine>;\
            <A>;<B>;<C>;<D>;<E>;<F>;\
            <a>;<b>;<c>;<d>;<e>;<f>

    blank   <space>;\
            <tab>

    toupper (<a>,<A>);(<b>,<B>);(<c>,<C>);(<d>,<D>);(<e>,<E>);\
            (<f>,<F>);(<g>,<G>);(<h>,<H>);(<i>,<I>);(<j>,<J>);\
            (<k>,<K>);(<l>,<L>);(<m>,<M>);(<n>,<N>);(<o>,<O>);\
            (<p>,<P>);(<q>,<Q>);(<r>,<R>);(<s>,<S>);(<t>,<T>);\
            (<u>,<U>);(<v>,<V>);(<w>,<W>);(<x>,<X>);(<y>,<Y>);\
            (<z>,<Z>)

    tolower (<A>,<a>);(<B>,<b>);(<C>,<c>);(<D>,<d>);(<E>,<e>);\
            (<F>,<f>);(<G>,<g>);(<H>,<h>);(<I>,<i>);(<J>,<j>);\
            (<K>,<k>);(<L>,<l>);(<M>,<m>);(<N>,<n>);(<O>,<o>);\
            (<P>,<p>);(<Q>,<q>);(<R>,<r>);(<S>,<s>);(<T>,<t>);\
            (<U>,<u>);(<V>,<v>);(<W>,<w>);(<X>,<x>);(<Y>,<y>);\
            (<Z>,<z>)

    END LC_CTYPE

    #############
    LC_COLLATE
    #############

    order_start
    # ASCII Control characters
    <NUL>
    <SOH>
    <STX>
    <ETX>
    <EOT>
    <ENQ>
    <ACK>
    <alert>
    <backspace>
    <tab>
    <newline>
    <vertical-tab>
    <form-feed>
    <carriage-return>
    <SO>
    <SI>
    <DLE>
    <DC1>
    <DC2>
    <DC3>
    <DC4>
    <NAK>
    <SYN>
    <ETB>
    <CAN>
    <EM>
    <SUB>
    <ESC>
    <IS4>
    <IS3>
    <IS2>
    <IS1>
    <space>
    <exclamation-mark>
    <quotation-mark>
    <number-sign>
    <dollar-sign>
    <percent-sign>
    <ampersand>
    <apostrophe>
    <left-parenthesis>
    <right-parenthesis>
    <asterisk>
    <plus-sign>
    <comma>
    <hyphen>
    <period>
    <slash>
    <zero>
    <one>
    <two>
    <three>
    <four>
    <five>
    <six>
    <seven>
    <eight>
    <nine>
    <colon>
    <semicolon>
    <less-than-sign>
    <equals-sign>
    <greater-than-sign>
    <question-mark>
    <commercial-at>
    <A>
    <B>
    <C>
    <D>
    <E>
    <F>
    <G>
    <H>
    <I>
    <J>
    <K>
    <L>
    <M>
    <N>
    <O>
    <P>
    <Q>
    <R>
    <S>
    <T>
    <U>
    <V>
    <W>
    <X>
    <Y>
    <Z>
    <left-square-bracket>
    <backslash>
    <right-square-bracket>
    <circumflex>
    <underscore>
    <grave-accent>
    <a>
    <b>
    <c>
    <d>
    <e>
    <f>
    <g>
    <h>
    <i>
    <j>
    <k>
    <l>
    <m>
    <n>
    <o>
    <p>
    <q>
    <r>
    <s>
    <t>
    <u>
    <v>
    <w>
    <x>
    <y>
    <z>
    <left-curly-bracket>
    <vertical-line>
    <right-curly-bracket>
    <tilde>
    <DEL>
    order_end

    END LC_COLLATE

    #############
    LC_MONETARY
    #############

    int_curr_symbol   ""
    currency_symbol   ""
    mon_decimal_point ""
    mon_thousands_sep ""
    mon_grouping      ""
    positive_sign     ""
    negative_sign     ""
    int_frac_digits   -1
    frac_digits       -1
    p_cs_precedes     -1
    p_sep_by_space    -1
    n_cs_precedes     -1
    n_sep_by_space    -1
    p_sign_posn       -1
    n_sign_posn       -1

    END LC_MONETARY

    #############
    LC_NUMERIC
    #############

    decimal_point     "<period>"
    thousands_sep     ""
    grouping          ""

    END LC_NUMERIC

    #############
    LC_TIME
    #############

    abday   "<S><u><n>";\
            "<M><o><n>";\
            "<T><u><e>";\
            "<W><e><d>";\
            "<T><h><u>";\
            "<F><r><i>";\
            "<S><a><t>"

    day     "<S><u><n><d><a><y>";\
            "<M><o><n><d><a><y>";\
            "<T><u><e><s><d><a><y>";\
            "<W><e><d><n><e><s><d><a><y>";\
            "<T><h><u><r><s><d><a><y>";\
            "<F><r><i><d><a><y>";\
            "<S><a><t><u><r><d><a><y>"

    abmon   "<J><a><n>";\
            "<F><e><b>";\
            "<M><a><r>";\
            "<A><p><r>";\
            "<M><a><y>";\
            "<J><u><n>";\
            "<J><u><l>";\
            "<A><u><g>";\
            "<S><e><p>";\
            "<O><c><t>";\
            "<N><o><v>";\
            "<D><e><c>"

    mon     "<J><a><n><u><a><r><y>";\
            "<F><e><b><r><u><a><r><y>";\
            "<M><a><r><c><h>";\
            "<A><p><r><i><l>";\
            "<M><a><y>";\
            "<J><u><n><e>";\
            "<J><u><l><y>";\
            "<A><u><g><u><s><t>";\
            "<S><e><p><t><e><m><b><e><r>";\
            "<O><c><t><o><b><e><r>";\
            "<N><o><v><e><m><b><e><r>";\
            "<D><e><c><e><m><b><e><r>"

    # equivalent of AM/PM (%p)
    am_pm      "<A><M>";"<P><M>"

    # appropriate date and time representation (%c) "%a %b %e %H:%M:%S %Y"
    d_t_fmt    "<percent-sign><a><space><percent-sign><b><space><percent-sign><e>\
    <space><percent-sign><H><colon><percent-sign><M>\
    <colon><percent-sign><S><space><percent-sign><Y>"

    # appropriate date representation (%x) "%m/%d/%y"
    d_fmt      "<percent-sign><m><slash><percent-sign><d><slash><percent-sign><y>"

    # appropriate time representation (%X) "%H:%M:%S"
    t_fmt      "<percent-sign><M><colon><percent-sign><M><colon><percent-sign><S>"

    # appropriate 12-hour time representation (%r) "%I:%M:%S %p"
    t_fmt_ampm "<percent-sign><I><colon><percent-sign><M><colon><percent-sign><S>\
    <space><percent-sign><p>"

    END LC_TIME

    #############
    LC_MESSAGES
    #############

    yesexpr "<circumflex><left-square-bracket><y><Y><right-square-bracket>"
    noexpr  "<circumflex><left-square-bracket><n><N><right-square-bracket>"

    END LC_MESSAGES

    #############
    LC_SYNTAX
    #############

    backslash     "<backslash>"
    right_brace   "<right-brace>"
    left_brace    "<left-brace>"
    right_bracket "<right-square-bracket>"
    left_bracket  "<left-square-bracket>"
    circumflex    "<circumflex>"
    tilde         "<tilde>"
    exclamation_mark "<exclamation-mark>"
    number_sign   "<number-sign>"
    vertical_line "<vertical-line>"
    dollar_sign   "<dollar-sign>"
    commercial_at "<commercial-at>"
    grave_accent  "<grave-accent>"

    END LC-SYNTAX

    #############
    LC_TOD
    #############

    timezone_difference  0
    timezone_name        ""
    daylight_name        ""
    start_month          0
    end_month            0
    start_week           0
    end_week             0
    start_day            0
    end_day              0
    start_time           0
    end_time             0
    shift                0

    END LC_TOD

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