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Diffstat (limited to 'man/man3/getnetent_r.3')
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diff --git a/man/man3/getnetent_r.3 b/man/man3/getnetent_r.3 new file mode 100644 index 000000000..d8f70c3a2 --- /dev/null +++ b/man/man3/getnetent_r.3 @@ -0,0 +1,150 @@ +'\" t +.\" Copyright 2008, Linux Foundation, written by Michael Kerrisk +.\" <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH getnetent_r 3 (date) "Linux man-pages (unreleased)" +.SH NAME +getnetent_r, getnetbyname_r, getnetbyaddr_r \- get +network entry (reentrant) +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <netdb.h> +.P +.BI "int getnetent_r(struct netent *restrict " result_buf , +.BI " char " buf "[restrict ." buflen "], size_t " buflen , +.BI " struct netent **restrict " result , +.BI " int *restrict " h_errnop ); +.BI "int getnetbyname_r(const char *restrict " name , +.BI " struct netent *restrict " result_buf , +.BI " char " buf "[restrict ." buflen "], size_t " buflen , +.BI " struct netent **restrict " result , +.BI " int *restrict " h_errnop ); +.BI "int getnetbyaddr_r(uint32_t " net ", int " type , +.BI " struct netent *restrict " result_buf , +.BI " char " buf "[restrict ." buflen "], size_t " buflen , +.BI " struct netent **restrict " result , +.BI " int *restrict " h_errnop ); +.P +.fi +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR getnetent_r (), +.BR getnetbyname_r (), +.BR getnetbyaddr_r (): +.nf + Since glibc 2.19: + _DEFAULT_SOURCE + glibc 2.19 and earlier: + _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +The +.BR getnetent_r (), +.BR getnetbyname_r (), +and +.BR getnetbyaddr_r () +functions are the reentrant equivalents of, respectively, +.BR getnetent (3), +.BR getnetbyname (3), +and +.BR getnetbynumber (3). +They differ in the way that the +.I netent +structure is returned, +and in the function calling signature and return value. +This manual page describes just the differences from +the nonreentrant functions. +.P +Instead of returning a pointer to a statically allocated +.I netent +structure as the function result, +these functions copy the structure into the location pointed to by +.IR result_buf . +.P +The +.I buf +array is used to store the string fields pointed to by the returned +.I netent +structure. +(The nonreentrant functions allocate these strings in static storage.) +The size of this array is specified in +.IR buflen . +If +.I buf +is too small, the call fails with the error +.BR ERANGE , +and the caller must try again with a larger buffer. +(A buffer of length 1024 bytes should be sufficient for most applications.) +.\" I can find no information on the required/recommended buffer size; +.\" the nonreentrant functions use a 1024 byte buffer -- mtk. +.P +If the function call successfully obtains a network record, then +.I *result +is set pointing to +.IR result_buf ; +otherwise, +.I *result +is set to NULL. +.P +The buffer pointed to by +.I h_errnop +is used to return the value that would be stored in the global variable +.I h_errno +by the nonreentrant versions of these functions. +.\" getnetent.3 doesn't document any use of h_errno, but nevertheless +.\" the nonreentrant functions no seem to set h_errno. +.SH RETURN VALUE +On success, these functions return 0. +On error, they return one of the positive error numbers listed in ERRORS. +.P +On error, record not found +.RB ( getnetbyname_r (), +.BR getnetbyaddr_r ()), +or end of input +.RB ( getnetent_r ()) +.I result +is set to NULL. +.SH ERRORS +.TP +.B ENOENT +.RB ( getnetent_r ()) +No more records in database. +.TP +.B ERANGE +.I buf +is too small. +Try again with a larger buffer +(and increased +.IR buflen ). +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR getnetent_r (), +.BR getnetbyname_r (), +.BR getnetbyaddr_r () +T} Thread safety MT-Safe locale +.TE +.SH VERSIONS +Functions with similar names exist on some other systems, +though typically with different calling signatures. +.SH STANDARDS +GNU. +.SH SEE ALSO +.BR getnetent (3), +.BR networks (5) |