ndelay_on(3) Library Functions Manual ndelay_on(3)NAME
ndelay_on - put file descriptor in non-blocking mode
SYNTAX
#include <ndelay.h>
extern int ndelay_on(int fd);
DESCRIPTION
ndelay_on puts a file descriptor in non-blocking mode. Reading from and writing to non-blocking network sockets, FIFOs or device files
will return immediately, even if not as many bytes have been processed as were specified.
If an error occurred, ndelay_on will return nonzero and set errno accordingly.
SEE ALSO fcntl(2), ndelay_off(3)ndelay_on(3)
Check Out this Related Man Page
PCAP_SETNONBLOCK(3PCAP)PCAP_SETNONBLOCK(3PCAP)NAME
pcap_setnonblock, pcap_getnonblock - set or get the state of non-blocking mode on a capture device
SYNOPSIS
#include <pcap/pcap.h>
char errbuf[PCAP_ERRBUF_SIZE];
int pcap_setnonblock(pcap_t *p, int nonblock, char *errbuf);
int pcap_getnonblock(pcap_t *p, char *errbuf);
DESCRIPTION
pcap_setnonblock() puts a capture handle into ``non-blocking'' mode, or takes it out of ``non-blocking'' mode, depending on whether the
nonblock argument is non-zero or zero. It has no effect on ``savefiles''. If there is an error, -1 is returned and errbuf is filled in
with an appropriate error message; otherwise, 0 is returned. In ``non-blocking'' mode, an attempt to read from the capture descriptor with
pcap_dispatch() will, if no packets are currently available to be read, return 0 immediately rather than blocking waiting for packets to
arrive. pcap_loop() and pcap_next() will not work in ``non-blocking'' mode.
When first activated with pcap_activate() or opened with pcap_open_live() , a capture handle is not in ``non-blocking mode''; a call to
pcap_setnonblock() is required in order to put it into ``non-blocking'' mode.
RETURN VALUE
pcap_getnonblock() returns the current ``non-blocking'' state of the capture descriptor; it always returns 0 on ``savefiles''. If there is
an error, -1 is returned and errbuf is filled in with an appropriate error message.
errbuf is assumed to be able to hold at least PCAP_ERRBUF_SIZE chars.
SEE ALSO pcap(3PCAP), pcap_loop(3PCAP), pcap_next_ex(3PCAP), pcap_geterr(3PCAP)
18 October 2014 PCAP_SETNONBLOCK(3PCAP)
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