table of contents
explain_adjtimex(3) | Library Functions Manual | explain_adjtimex(3) |
NAME¶
explain_adjtimex - explain adjtimex(2) errorsSYNOPSIS¶
#include <libexplain/adjtimex.h>DESCRIPTION¶
These functions may be used to obtain explanations for errors returned by the adjtimex(2) system call.explain_adjtimex¶
const char *explain_adjtimex(struct timex *data); The explain_adjtimex function is used to obtain an explanation of an error returned by the adjtimex(2) 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.- data
- The original data, exactly as passed to the adjtimex(2) 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.
int result = adjtimex(data);
{
fprintf(stderr, "%s\n", explain_adjtimex(data));
exit(EXIT_FAILURE); }
explain_errno_adjtimex¶
const char *explain_errno_adjtimex(int errnum, struct timex *data); The explain_errno_adjtimex function is used to obtain an explanation of an error returned by the adjtimex(2) 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.
- data
- The original data, exactly as passed to the adjtimex(2) 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.
int result = adjtimex(data);
{ int err = errno;
fprintf(stderr, "%s\n", explain_errno_adjtimex(err, data));
exit(EXIT_FAILURE); }
explain_message_adjtimex¶
void explain_message_adjtimex(char *message, int message_size, struct timex *data); The explain_message_adjtimex function is used to obtain an explanation of an error returned by the adjtimex(2) 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.
- data
- The original data, exactly as passed to the adjtimex(2) system call.
int result = adjtimex(data);
{ char message[3000];explain_message_adjtimex(message, sizeof(message), data);
fprintf(stderr, "%s\n", message); exit(EXIT_FAILURE); }
explain_message_errno_adjtimex¶
void explain_message_errno_adjtimex(char *message, int message_size, int errnum, struct timex *data); The explain_message_errno_adjtimex function is used to obtain an explanation of an error returned by the adjtimex(2) 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.
- data
- The original data, exactly as passed to the adjtimex(2) system call.
int result = adjtimex(data);
{ int err = errno; char message[3000];explain_message_errno_adjtimex(message, sizeof(message), err, data);
fprintf(stderr, "%s\n", message); exit(EXIT_FAILURE); }
SEE ALSO¶
- adjtimex(2)
- tune kernel clock
- explain_adjtimex_or_die(3)
- tune kernel clock and report errors