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Full Discussion: write() / read() syntax
Special Forums IP Networking write() / read() syntax Post 302419433 by jim mcnamara on Friday 7th of May 2010 06:59:09 AM
Old 05-07-2010
1. use send() & recv() on sockets they are meant for that and return more meaningfull error codes.

2. the syntax for write does not include a format string like:"%d %d" - the same is true for read
example:
Code:
retval=write(newsockfd, buffer, number_bytes_to_write);
retval=read (newsockfd, buffer, number_bytes_to_read);
retval=send(sockfd, buffer, bufferlen, 0);
retval=recv(newsockfd, buffer, bufferlen, 0);

You code cannot have compiled at all. Always check the return code from system calls. The 0 (flags argument) for recv lets you do neat stuff like MSG_PEEK.
 

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LEARN ABOUT CENTOS

papi_add_event

PAPI_add_event(3)						       PAPI							 PAPI_add_event(3)

NAME

       PAPI_add_event -

       add PAPI preset or native hardware event to an event set

SYNOPSIS

Detailed Description
       @par C Interface:
       int PAPI_add_event( int	EventSet, int  EventCode );

       PAPI_add_event adds one event to a PAPI Event Set. @n
       A hardware event can be either a PAPI preset or a native hardware event code.
       For a list of PAPI preset events, see PAPI_presets or run the avail test case
       in the PAPI distribution. PAPI presets can be passed to PAPI_query_event to see
       if they exist on the underlying architecture.
       For a list of native events available on current platform, run the papi_native_avail
       utility in the PAPI distribution. For the encoding of native events,
       see PAPI_event_name_to_code to learn how to generate native code for the
       supported native event on the underlying architecture.

       @param EventSet
	   An integer handle for a PAPI Event Set as created by PAPI_create_eventset.
       @param EventCode
	   A defined event such as PAPI_TOT_INS.

       @retval Positive-Integer
	   The number of consecutive elements that succeeded before the error.
       @retval PAPI_EINVAL
	   One or more of the arguments is invalid.
       @retval PAPI_ENOMEM
	   Insufficient memory to complete the operation.
       @retval PAPI_ENOEVST
	   The event set specified does not exist.
       @retval PAPI_EISRUN
	   The event set is currently counting events.
       @retval PAPI_ECNFLCT
	   The underlying counter hardware can not count this event and other events
	   in the event set simultaneously.
       @retval PAPI_ENOEVNT
	   The PAPI preset is not available on the underlying hardware.
       @retval PAPI_EBUG
	   Internal error, please send mail to the developers.

       @par Examples:

       *   int EventSet = PAPI_NULL;
       *   unsigned int native = 0x0;
       *   if ( PAPI_create_eventset( &EventSet ) != PAPI_OK )
       *   handle_error( 1 );
       *   // Add Total Instructions Executed to our EventSet
       *   if ( PAPI_add_event( EventSet, PAPI_TOT_INS ) != PAPI_OK )
       *   handle_error( 1 );
       *   // Add native event PM_CYC to EventSet
       *   if ( PAPI_event_name_to_code( "PM_CYC", &native ) != PAPI_OK )
       *   handle_error( 1 );
       *   if ( PAPI_add_event( EventSet, native ) != PAPI_OK )
       *   handle_error( 1 );
       *

       @see PAPI_cleanup_eventset @n
       PAPI_destroy_eventset @n
       PAPI_event_code_to_name @n
       PAPI_remove_events @n
       PAPI_query_event @n
       PAPI_presets @n
       PAPI_native @n
       PAPI_remove_event.fi

Author
       Generated automatically by Doxygen for PAPI from the source code.

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