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% PT_ALLOC_ENCODER(3)
<!---
! Copyright (c) 2015-2025, Intel Corporation
! SPDX-License-Identifier: BSD-3-Clause
!
! Redistribution and use in source and binary forms, with or without
! modification, are permitted provided that the following conditions are met:
!
! * Redistributions of source code must retain the above copyright notice,
! this list of conditions and the following disclaimer.
! * Redistributions in binary form must reproduce the above copyright notice,
! this list of conditions and the following disclaimer in the documentation
! and/or other materials provided with the distribution.
! * Neither the name of Intel Corporation nor the names of its contributors
! may be used to endorse or promote products derived from this software
! without specific prior written permission.
!
! THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
! AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
! LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
! CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
! SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
! INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
! CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
! ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
! POSSIBILITY OF SUCH DAMAGE.
!-->
# NAME
pt_alloc_encoder, pt_free_encoder - allocate/free an Intel(R) Processor Trace
packet encoder
# SYNOPSIS
| **\#include `<intel-pt.h>`**
|
| **struct pt_packet_encoder \***
| **pt_alloc_encoder(const struct pt_config \**config*);**
|
| **void pt_free_encoder(struct pt_packet_encoder \**encoder*);**
Link with *-lipt*.
# DESCRIPTION
**pt_alloc_encoder**() allocates a new Intel Processor Trace (Intel PT) packet
encoder and returns a pointer to it. The packet encoder generates Intel PT
trace from *pt_packet* objects. See **pt_enc_next**(3).
The *config* argument points to a *pt_config* object. See **pt_config**(3).
The *config* argument will not be referenced by the returned encoder but the
trace buffer defined by the *config* argument's *begin* and *end* fields will.
The returned packet encoder is initially synchronized onto the beginning of the
trace buffer specified in its *config* argument. Use **pt_enc_sync_set**(3) to
move it to any other position inside the trace buffer.
**pt_free_encoder**() frees the Intel PT packet encoder pointed to by encoder*.
*The *encoder* argument must be NULL or point to an encoder that has been
*allocated by a call to **pt_alloc_encoder**().
# RETURN VALUE
**pt_alloc_encoder**() returns a pointer to a *pt_packet_encoder* object on
success or NULL in case of an error.
# EXAMPLE
~~~{.c}
int foo(const struct pt_config *config) {
struct pt_packet_encoder *encoder;
errcode;
encoder = pt_alloc_encoder(config);
if (!encoder)
return pte_nomem;
errcode = bar(encoder);
pt_free_encoder(encoder);
return errcode;
}
~~~
# SEE ALSO
**pt_config**(3), **pt_enc_sync_set**(3), **pt_enc_get_offset**(3),
**pt_enc_get_config**(3), **pt_enc_next**(3)
|
