Merge

@appendixsubsec Changes in release 3.23.28

@itemize @bullet

@item

Added new options @code{--pager[=...]}, @code{--no-pager},

@code{--tee=...} and @code{--no-tee} to the @code{mysql} client.  The

new corresponding interactive commands are @code{pager}, @code{nopager},

@code{tee} and @code{notee}. @xref{mysql}, @code{mysql --help} and the

interactive help for more information.

@item

Fixed crash when automatic repair of @code{MyISAM} table failed.

@item

Fixed a major performance bug in the table locking code when one

#include <pthread.h>

#include <stdio.h>

#include <stdlib.h>

#include <unistd.h>

static void spawn_stern_thread(pthread_t *t);

static int act_goofy(void);

static void *be_stern(void *);

static struct {

  pthread_mutex_t lock;

  pthread_cond_t  cond;

  int msg;

} comm = { PTHREAD_MUTEX_INITIALIZER, PTHREAD_COND_INITIALIZER, 0 };

int

main(void)

{

  pthread_t t;

  spawn_stern_thread(&t);

  while (act_goofy() != 0)

    /* do nothing */;

  pthread_exit(NULL);

  /* notreached */

  return EXIT_SUCCESS;

}

static void spawn_stern_thread(pthread_t *t)

{

  pthread_attr_t attr;

  pthread_attr_init(&attr);

  pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

  if (pthread_create(t, &attr, be_stern, NULL) != 0)

    exit(EXIT_FAILURE);

  pthread_attr_destroy(&attr);

}

static int act_goofy(void)

{

  int  ret;

  char buf[30];

  fputs("Are you ready to act goofy (Y/n)? ", stdout); fflush(stdout);

  fgets(buf, sizeof(buf), stdin);

  pthread_mutex_lock(&comm.lock);

  if (buf[0] == 'y' || buf[0] == '\n') {

    fputs("** Waawlwalkwwwaa!!\n", stdout); fflush(stdout);

    ++comm.msg;

    ret = 1;

  }

  else {

    fputs("OK, I hate you.  Let me go.\n", stdout); fflush(stdout);

    comm.msg = -1;

    ret = 0;

  }

  pthread_mutex_unlock(&comm.lock);

  pthread_cond_signal(&comm.cond);

  return ret;

}

static void *be_stern(void *v __attribute((unused)))

{

  int msg;

  for (;;) {

    pthread_mutex_lock(&comm.lock);

    while (comm.msg == 0)

      pthread_cond_wait(&comm.cond, &comm.lock);

    msg = comm.msg;

    comm.msg = 0;

    pthread_mutex_unlock(&comm.lock);

    if (msg < 0)

      break;  /* the goofy one learned a lesson! */

    fputs("I HAVE TO BE STERN WITH YOU!\n", stderr);

    fprintf(stderr, "I should give you %d lashes.\n", msg);

    sleep(msg);

  }

  fputs("You are NOTHING!\n", stderr);

  return NULL;

}