libtraceevent-parse_head.txt (1942B)
1libtraceevent(3) 2================ 3 4NAME 5---- 6tep_parse_header_page - Parses the data stored in the header page. 7 8SYNOPSIS 9-------- 10[verse] 11-- 12*#include <event-parse.h>* 13 14int *tep_parse_header_page*(struct tep_handle pass:[*]_tep_, char pass:[*]_buf_, unsigned long _size_, int _long_size_); 15-- 16 17DESCRIPTION 18----------- 19The _tep_parse_header_page()_ function parses the header page data from _buf_, 20and initializes the _tep_, trace event parser context, with it. The buffer 21_buf_ is with _size_, and is supposed to be copied from 22tracefs/events/header_page. 23 24Some old kernels do not have header page info, in this case the 25_tep_parse_header_page()_ function can be called with _size_ equal to 0. The 26_tep_ context is initialized with default values. The _long_size_ can be used in 27this use case, to set the size of a long integer to be used. 28 29RETURN VALUE 30------------ 31The _tep_parse_header_page()_ function returns 0 in case of success, or -1 32in case of an error. 33 34EXAMPLE 35------- 36[source,c] 37-- 38#include <event-parse.h> 39... 40struct tep_handle *tep = tep_alloc(); 41... 42char *buf; 43int size; 44buf = read_file("/sys/kernel/tracing/events/header_page", &size); 45if (tep_parse_header_page(tep, buf, size, sizeof(unsigned long)) != 0) { 46 /* Failed to parse the header page */ 47} 48... 49-- 50 51FILES 52----- 53[verse] 54-- 55*event-parse.h* 56 Header file to include in order to have access to the library APIs. 57*-ltraceevent* 58 Linker switch to add when building a program that uses the library. 59-- 60 61SEE ALSO 62-------- 63_libtraceevent(3)_, _trace-cmd(1)_ 64 65AUTHOR 66------ 67[verse] 68-- 69*Steven Rostedt* <rostedt@goodmis.org>, author of *libtraceevent*. 70*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>, author of this man page. 71-- 72REPORTING BUGS 73-------------- 74Report bugs to <linux-trace-devel@vger.kernel.org> 75 76LICENSE 77------- 78libtraceevent is Free Software licensed under the GNU LGPL 2.1 79 80RESOURCES 81--------- 82https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git