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Revision 1.1 by root, Tue Mar 8 20:17:17 2005 UTC vs.
Revision 1.4 by root, Tue Aug 15 07:29:06 2017 UTC

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61 utf8_length scalar 61 utf8_length scalar
62 Returns the number of characters in the string, counting wide UTF8 62 Returns the number of characters in the string, counting wide UTF8
63 characters as a single character, independent of wether the scalar 63 characters as a single character, independent of wether the scalar
64 is marked as containing bytes or mulitbyte characters. 64 is marked as containing bytes or mulitbyte characters.
65 65
66 $old = readonly scalar[, $new]
67 Returns whether the scalar is currently readonly, and sets or clears
68 the readonly status if a new status is given.
69
70 readonly_on scalar
71 Sets the readonly flag on the scalar.
72
73 readonly_off scalar
74 Clears the readonly flag on the scalar.
75
66 unmagic scalar, type 76 unmagic scalar, type
67 Remove the specified magic from the scalar (DANGEROUS!). 77 Remove the specified magic from the scalar (DANGEROUS!).
68 78
69 weaken scalar 79 weaken scalar
70 Weaken a reference. (See also WeakRef). 80 Weaken a reference. (See also WeakRef).
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76 returns true when the scalar is tainted, false otherwise. 86 returns true when the scalar is tainted, false otherwise.
77 87
78 untaint scalar 88 untaint scalar
79 Remove the tainted flag from the specified scalar. 89 Remove the tainted flag from the specified scalar.
80 90
91 length = len scalar
92 Returns SvLEN (scalar), that is, the actual number of bytes
93 allocated to the string value, or "undef", is the scalar has no
94 string value.
95
81 grow scalar, newlen 96 scalar = grow scalar, newlen
82 Sets the memory area used for the scalar to the given length, if the 97 Sets the memory area used for the scalar to the given length, if the
83 current length is less than the new value. This does not affect the 98 current length is less than the new value. This does not affect the
84 contents of the scalar, but is only useful to "pre-allocate" memory 99 contents of the scalar, but is only useful to "pre-allocate" memory
85 space if you know the scalar will grow. The return value is the 100 space if you know the scalar will grow. The return value is the
86 modified scalar (the scalar is modified in-place). 101 modified scalar (the scalar is modified in-place).
102
103 scalar = extend scalar, addlen=64
104 Reserves enough space in the scalar so that addlen bytes can be
105 appended without reallocating it. The actual contents of the scalar
106 will not be affected. The modified scalar will also be returned.
107
108 This function is meant to make append workloads efficient - if you
109 append a short string to a scalar many times (millions of times),
110 then perl will have to reallocate and copy the scalar basically
111 every time.
112
113 If you instead use "extend $scalar, length $shortstring", then
114 Convert::Scalar will use a "size to next power of two, roughly"
115 algorithm, so as the scalar grows, perl will have to resize and copy
116 it less and less often.
117
118 nread = extend_read fh, scalar, addlen=64
119 Calls "extend scalar, addlen" to ensure some space is available,
120 then do the equivalent of "sysread" to the end, to try to fill the
121 extra space. Returns how many bytes have been read, 0 on EOF or
122 undef> on eror, just like "sysread".
123
124 This function is useful to implement many protocols where you read
125 some data, see if it is enough to decode, and if not, read some
126 more, where the naive or easy way of doing this would result in bad
127 performance.
128
129 nread = read_all fh, scalar, length
130 Tries to read "length" bytes into "scalar". Unlike "read" or
131 "sysread", it will try to read more bytes if not all bytes could be
132 read in one go (this is often called "xread" in C).
133
134 Returns the total nunmber of bytes read (normally "length", unless
135 an error or EOF occured), 0 on EOF and "undef" on errors.
136
137 nwritten = write_all fh, scalar
138 Like "readall", but for writes - the equivalent of the "xwrite"
139 function often seen in C.
87 140
88 refcnt scalar[, newrefcnt] 141 refcnt scalar[, newrefcnt]
89 Returns the current reference count of the given scalar and 142 Returns the current reference count of the given scalar and
90 optionally sets it to the given reference count. 143 optionally sets it to the given reference count.
91 144
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98 Better yet: don't use this module in this case. 151 Better yet: don't use this module in this case.
99 152
100 refcnt_rv scalar[, newrefcnt] 153 refcnt_rv scalar[, newrefcnt]
101 Works like "refcnt", but dereferences the given reference first. 154 Works like "refcnt", but dereferences the given reference first.
102 This is useful to find the reference count of arrays or hashes, 155 This is useful to find the reference count of arrays or hashes,
103 which cnanot be passed directly. Remember that taking a reference of 156 which cannot be passed directly. Remember that taking a reference of
104 some object increases it's reference count, so the reference count 157 some object increases it's reference count, so the reference count
105 used by the *_rv-functions tend to be one higher. 158 used by the *_rv-functions tend to be one higher.
106 159
107 refcnt_inc_rv scalar 160 refcnt_inc_rv scalar
108 Works like "refcnt_inc", but dereferences the given reference first. 161 Works like "refcnt_inc", but dereferences the given reference first.

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