man3/getrpcent_r.3

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  26 .TH GETRPCENT_R 3  2017-09-15 "GNU" "Linux Programmer's Manual"
  27 .SH NAME
  28 getrpcent_r, getrpcbyname_r, getrpcbynumber_r \- get
  29 RPC entry (reentrant)
  30 .SH SYNOPSIS
  31 .nf
  32 .B #include <netdb.h>
  33 .PP
  34 .BI "int getrpcent_r(struct rpcent *" result_buf ", char *" buf ,
  35 .BI "                size_t " buflen ", struct rpcent **" result );
  36 .BI "int getrpcbyname_r(const char *" name ,
  37 .BI "                struct rpcent *" result_buf ", char *" buf ,
  38 .BI "                size_t " buflen ", struct rpcent **" result );
  39 .BI "int getrpcbynumber_r(int " number ,
  40 .BI "                struct rpcent *" result_buf ", char *" buf ,
  41 .BI "                size_t " buflen ", struct rpcent **" result );
  42 .PP
  43 .fi
  44 .RS -4
  45 Feature Test Macro Requirements for glibc (see
  46 .BR feature_test_macros (7)):
  47 .ad l
  48 .RE
  49 .PP
  50 .BR getrpcent_r (),
  51 .BR getrpcbyname_r (),
  52 .BR getrpcbynumber_r ():
  53     Since glibc 2.19:
  54         _DEFAULT_SOURCE
  55     Glibc 2.19 and earlier:
  56         _BSD_SOURCE || _SVID_SOURCE
  57 .ad b
  58 .SH DESCRIPTION
  59 The
  60 .BR getrpcent_r (),
  61 .BR getrpcbyname_r (),
  62 and
  63 .BR getrpcbynumber_r ()
  64 functions are the reentrant equivalents of, respectively,
  65 .BR getrpcent (3),
  66 .BR getrpcbyname (3),
  67 and
  68 .BR getrpcbynumber (3).
  69 They differ in the way that the
  70 .I rpcent
  71 structure is returned,
  72 and in the function calling signature and return value.
  73 This manual page describes just the differences from
  74 the nonreentrant functions.
  75 .PP
  76 Instead of returning a pointer to a statically allocated
  77 .I rpcent
  78 structure as the function result,
  79 these functions copy the structure into the location pointed to by
  80 .IR result_buf .
  81 .PP
  82 The
  83 .I buf
  84 array is used to store the string fields pointed to by the returned
  85 .I rpcent
  86 structure.
  87 (The nonreentrant functions allocate these strings in static storage.)
  88 The size of this array is specified in
  89 .IR buflen .
  90 If
  91 .I buf
  92 is too small, the call fails with the error
  93 .BR ERANGE ,
  94 and the caller must try again with a larger buffer.
  95 (A buffer of length 1024 bytes should be sufficient for most applications.)
  96 .\" I can find no information on the required/recommended buffer size;
  97 .\" the nonreentrant functions use a 1024 byte buffer -- mtk.
  98 .PP
  99 If the function call successfully obtains an RPC record, then
 100 .I *result
 101 is set pointing to
 102 .IR result_buf ;
 103 otherwise,
 104 .I *result
 105 is set to NULL.
 106 .SH RETURN VALUE
 107 On success, these functions return 0.
 108 On error, they return one of the positive error numbers listed in ERRORS.
 109 .PP
 110 On error, record not found
 111 .RB ( getrpcbyname_r (),
 112 .BR getrpcbynumber_r ()),
 113 or end of input
 114 .RB ( getrpcent_r ())
 115 .I result
 116 is set to NULL.
 117 .SH ERRORS
 118 .TP
 119 .B ENOENT
 120 .RB ( getrpcent_r ())
 121 No more records in database.
 122 .TP
 123 .B ERANGE
 124 .I buf
 125 is too small.
 126 Try again with a larger buffer
 127 (and increased
 128 .IR buflen ).
 129 .SH ATTRIBUTES
 130 For an explanation of the terms used in this section, see
 131 .BR attributes (7).
 132 .ad l
 133 .TS
 134 allbox;
 135 lbw19 lb lb
 136 l l l.
 137 Interface       Attribute       Value
 138 T{
 139 .BR getrpcent_r (),
 140 .BR getrpcbyname_r (),
 141 .BR getrpcbynumber_r ()
 142 T}      Thread safety   MT-Safe locale
 143 .TE
 144 .ad
 145 .SH CONFORMING TO
 146 These functions are GNU extensions.
 147 Functions with similar names exist on some other systems,
 148 though typically with different calling signatures.
 149 .SH SEE ALSO
 150 .BR getrpcent (3),
 151 .BR rpc (5)