noblock.c

Go to the documentation of this file.

/*-------------------------------------------------------------------------
 *
 * noblock.c
 *    set a file descriptor as blocking or non-blocking
 *
 * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * IDENTIFICATION
 *    src/port/noblock.c
 *
 *-------------------------------------------------------------------------
 */
 
#include "c.h"
 
#include <fcntl.h>
 
 
/*
 * Put socket into nonblock mode.
 * Returns true on success, false on failure.
 */
bool
pg_set_noblock(pgsocket sock)
{
#if !defined(WIN32)
    int         flags;
 
    flags = fcntl(sock, F_GETFL);
    if (flags < 0)
        return false;
    if (fcntl(sock, F_SETFL, (flags | O_NONBLOCK)) == -1)
        return false;
    return true;
#else
    unsigned long ioctlsocket_ret = 1;
 
    /* Returns non-0 on failure, while fcntl() returns -1 on failure */
    return (ioctlsocket(sock, FIONBIO, &ioctlsocket_ret) == 0);
#endif
}
 
/*
 * Put socket into blocking mode.
 * Returns true on success, false on failure.
 */
bool
pg_set_block(pgsocket sock)
{
#if !defined(WIN32)
    int         flags;
 
    flags = fcntl(sock, F_GETFL);
    if (flags < 0)
        return false;
    if (fcntl(sock, F_SETFL, (flags & ~O_NONBLOCK)) == -1)
        return false;
    return true;
#else
    unsigned long ioctlsocket_ret = 0;
 
    /* Returns non-0 on failure, while fcntl() returns -1 on failure */
    return (ioctlsocket(sock, FIONBIO, &ioctlsocket_ret) == 0);
#endif
}