| /*------------------------------------------------------------------------- |
| * |
| * pgsleep.c |
| * Portable delay handling. |
| * |
| * |
| * Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group |
| * |
| * $PostgreSQL: pgsql/src/port/pgsleep.c,v 1.12 2009/01/01 17:24:04 momjian Exp $ |
| * |
| *------------------------------------------------------------------------- |
| */ |
| #include "c.h" |
| |
| #include <unistd.h> |
| #include <sys/time.h> |
| |
| /* |
| * In a Windows backend, we don't use this implementation, but rather |
| * the signal-aware version in src/backend/port/win32/signal.c. |
| */ |
| #if defined(FRONTEND) || !defined(WIN32) |
| |
| /* |
| * pg_usleep --- delay the specified number of microseconds. |
| * |
| * NOTE: although the delay is specified in microseconds, the effective |
| * resolution is only 1/HZ, or 10 milliseconds, on most Unixen. Expect |
| * the requested delay to be rounded up to the next resolution boundary. |
| * |
| * On machines where "long" is 32 bits, the maximum delay is ~2000 seconds. |
| */ |
| void |
| pg_usleep(long microsec) |
| { |
| if (microsec > 0) |
| { |
| #ifndef WIN32 |
| struct timeval delay; |
| |
| delay.tv_sec = microsec / 1000000L; |
| delay.tv_usec = microsec % 1000000L; |
| (void) select(0, NULL, NULL, NULL, &delay); |
| #else |
| SleepEx((microsec < 500 ? 1 : (microsec + 500) / 1000), FALSE); |
| #endif |
| } |
| } |
| |
| #endif /* defined(FRONTEND) || !defined(WIN32) */ |