Provided by: libexplain-dev_1.4.D001-7_amd64 
NAME
explain_acl_to_text - explain acl_to_text(3) errors
SYNOPSIS
#include <libexplain/acl_to_text.h>
const char *explain_acl_to_text(acl_t acl, ssize_t *len_p);
const char *explain_errno_acl_to_text(int errnum, acl_t acl, ssize_t *len_p);
void explain_message_acl_to_text(char *message, int message_size, acl_t acl, ssize_t
*len_p);
void explain_message_errno_acl_to_text(char *message, int message_size, int errnum, acl_t
acl, ssize_t *len_p);
DESCRIPTION
These functions may be used to obtain explanations for errors returned by the
acl_to_text(3) system call.
explain_acl_to_text
const char *explain_acl_to_text(acl_t acl, ssize_t *len_p);
The explain_acl_to_text function is used to obtain an explanation of an error returned by
the acl_to_text(3) system call. The least the message will contain is the value of
strerror(errno), but usually it will do much better, and indicate the underlying cause in
more detail.
The errno global variable will be used to obtain the error value to be decoded.
acl The original acl, exactly as passed to the acl_to_text(3) system call.
len_p The original len_p, exactly as passed to the acl_to_text(3) system call.
Returns:
The message explaining the error. This message buffer is shared by all libexplain
functions which do not supply a buffer in their argument list. This will be
overwritten by the next call to any libexplain function which shares this buffer,
including other threads.
Note: This function is not thread safe, because it shares a return buffer across all
threads, and many other functions in this library.
Example: This function is intended to be used in a fashion similar to the following
example:
char *result = acl_to_text(acl, len_p);
if (!result)
{
fprintf(stderr, "%s\n", explain_acl_to_text(acl, len_p));
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_acl_to_text_or_die(3)
function.
explain_errno_acl_to_text
const char *explain_errno_acl_to_text(int errnum, acl_t acl, ssize_t *len_p);
The explain_errno_acl_to_text function is used to obtain an explanation of an error
returned by the acl_to_text(3) system call. The least the message will contain is the
value of strerror(errno), but usually it will do much better, and indicate the underlying
cause in more detail.
errnum The error value to be decoded, usually obtained from the errno global variable
just before this function is called. This is necessary if you need to call any
code between the system call to be explained and this function, because many libc
functions will alter the value of errno.
acl The original acl, exactly as passed to the acl_to_text(3) system call.
len_p The original len_p, exactly as passed to the acl_to_text(3) system call.
Returns:
The message explaining the error. This message buffer is shared by all libexplain
functions which do not supply a buffer in their argument list. This will be
overwritten by the next call to any libexplain function which shares this buffer,
including other threads.
Note: This function is not thread safe, because it shares a return buffer across all
threads, and many other functions in this library.
Example: This function is intended to be used in a fashion similar to the following
example:
char *result = acl_to_text(acl, len_p);
if (!result)
{
int err = errno;
fprintf(stderr, "%s\n", explain_errno_acl_to_text(err, acl, len_p));
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_acl_to_text_or_die(3)
function.
explain_message_acl_to_text
void explain_message_acl_to_text(char *message, int message_size, acl_t acl, ssize_t
*len_p);
The explain_message_acl_to_text function is used to obtain an explanation of an error
returned by the acl_to_text(3) system call. The least the message will contain is the
value of strerror(errno), but usually it will do much better, and indicate the underlying
cause in more detail.
The errno global variable will be used to obtain the error value to be decoded.
message The location in which to store the returned message. If a suitable message return
buffer is supplied, this function is thread safe.
message_size
The size in bytes of the location in which to store the returned message.
acl The original acl, exactly as passed to the acl_to_text(3) system call.
len_p The original len_p, exactly as passed to the acl_to_text(3) system call.
Example: This function is intended to be used in a fashion similar to the following
example:
char *result = acl_to_text(acl, len_p);
if (!result)
{
char message[3000];
explain_message_acl_to_text(message, sizeof(message), acl, len_p);
fprintf(stderr, "%s\n", message);
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_acl_to_text_or_die(3)
function.
explain_message_errno_acl_to_text
void explain_message_errno_acl_to_text(char *message, int message_size, int errnum, acl_t
acl, ssize_t *len_p);
The explain_message_errno_acl_to_text function is used to obtain an explanation of an
error returned by the acl_to_text(3) system call. The least the message will contain is
the value of strerror(errno), but usually it will do much better, and indicate the
underlying cause in more detail.
message The location in which to store the returned message. If a suitable message return
buffer is supplied, this function is thread safe.
message_size
The size in bytes of the location in which to store the returned message.
errnum The error value to be decoded, usually obtained from the errno global variable
just before this function is called. This is necessary if you need to call any
code between the system call to be explained and this function, because many libc
functions will alter the value of errno.
acl The original acl, exactly as passed to the acl_to_text(3) system call.
len_p The original len_p, exactly as passed to the acl_to_text(3) system call.
Example: This function is intended to be used in a fashion similar to the following
example:
char *result = acl_to_text(acl, len_p);
if (!result)
{
int err = errno;
char message[3000];
explain_message_errno_acl_to_text(message, sizeof(message), err, acl, len_p);
fprintf(stderr, "%s\n", message);
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_acl_to_text_or_die(3)
function.
SEE ALSO
acl_to_text(3)
convert an ACL to text
explain_acl_to_text_or_die(3)
convert an ACL to text and report errors
COPYRIGHT
libexplain version 1.4
Copyright (C) 2013 Peter Miller
explain_acl_to_text(3)