Provided by: libexplain-dev_1.4.D001-7_amd64 
NAME
explain_usleep - explain usleep(3) errors
SYNOPSIS
#include <libexplain/usleep.h>
const char *explain_usleep(long long usec);
const char *explain_errno_usleep(int errnum, long long usec);
void explain_message_usleep(char *message, int message_size, long long usec);
void explain_message_errno_usleep(char *message, int message_size, int errnum, long long
usec);
DESCRIPTION
These functions may be used to obtain explanations for errors returned by the usleep(3)
system call.
explain_usleep
const char *explain_usleep(long long usec);
The explain_usleep function is used to obtain an explanation of an error returned by the
usleep(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.
usec The original usec, exactly as passed to the usleep(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:
if (usleep(usec) < 0)
{
fprintf(stderr, "%s\n", explain_usleep(usec));
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_usleep_or_die(3) function.
explain_errno_usleep
const char *explain_errno_usleep(int errnum, long long usec);
The explain_errno_usleep function is used to obtain an explanation of an error returned by
the usleep(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.
usec The original usec, exactly as passed to the usleep(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:
if (usleep(usec) < 0)
{
int err = errno;
fprintf(stderr, "%s\n", explain_errno_usleep(err, usec));
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_usleep_or_die(3) function.
explain_message_usleep
void explain_message_usleep(char *message, int message_size, long long usec);
The explain_message_usleep function is used to obtain an explanation of an error returned
by the usleep(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.
usec The original usec, exactly as passed to the usleep(3) system call.
Example: This function is intended to be used in a fashion similar to the following
example:
if (usleep(usec) < 0)
{
char message[3000];
explain_message_usleep(message, sizeof(message), usec);
fprintf(stderr, "%s\n", message);
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_usleep_or_die(3) function.
explain_message_errno_usleep
void explain_message_errno_usleep(char *message, int message_size, int errnum, long long
usec);
The explain_message_errno_usleep function is used to obtain an explanation of an error
returned by the usleep(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.
usec The original usec, exactly as passed to the usleep(3) system call.
Example: This function is intended to be used in a fashion similar to the following
example:
if (usleep(usec) < 0)
{
int err = errno;
char message[3000];
explain_message_errno_usleep(message, sizeof(message), err, usec);
fprintf(stderr, "%s\n", message);
exit(EXIT_FAILURE);
}
The above code example is available pre-packaged as the explain_usleep_or_die(3) function.
SEE ALSO
usleep(3)
suspend execution for microsecond intervals
explain_usleep_or_die(3)
suspend execution for microsecond intervals and report errors
COPYRIGHT
libexplain version 1.4
Copyright (C) 2013 Peter Miller
explain_usleep(3)