1explain_pread_or_die(3) Library Functions Manual explain_pread_or_die(3)
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6 explain_pread_or_die - seek and read from a file descriptor and report
7 errors
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10 #include <libexplain/pread.h>
11 ssize_t explain_pread_or_die(int fildes, void *data, size_t data_size,
12 off_t offset);
13 ssize_t explain_pread_on_error(int fildes, void *data, size_t
14 data_size, off_t offset))
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17 The explain_pread_or_die function is used to call the pread(2) system
18 call. On failure an explanation will be printed to stderr, obtained
19 from the explain_pread(3) function, and then the process terminates by
20 calling exit(EXIT_FAILURE).
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22 The explain_pread_on_error function is used to call the pread(2) system
23 call. On failure an explanation will be printed to stderr, obtained
24 from the explain_pread(3) function, but still returns to the caller.
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26 fildes The fildes, exactly as to be passed to the pread(2) system
27 call.
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29 data The data, exactly as to be passed to the pread(2) system call.
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31 data_size
32 The data_size, exactly as to be passed to the pread(2) system
33 call.
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35 offset The offset, exactly as to be passed to the pread(2) system
36 call.
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39 The explain_pread_or_die function only returns on success, see pread(2)
40 for more information. On failure, prints an explanation and exits, it
41 does not return.
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43 The explain_pread_on_error function always returns the value return by
44 the wrapped pread(2) system call.
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47 The explain_pread_or_die function is intended to be used in a fashion
48 similar to the following example:
49 ssize_t result = explain_pread_or_die(fildes, data, data_size, offset);
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52 pread(2)
53 read from a file descriptor at a given offset
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55 explain_pread(3)
56 explain pread(2) errors
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58 exit(2) terminate the calling process
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61 libexplain version 1.4
62 Copyright (C) 2009 Peter Miller
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66 explain_pread_or_die(3)