Open System Services System Calls Reference Manual (G06.29+, H06.08+, J06.03+)

System Functions (n - p) PUT_WRITEREADX(2)
NAME
PUT_WRITEREADX - Writes data to a Guardian file from an array and waits for data to be
read back from the file
LIBRARY
32-bit H-series and J-series OSS processes: /G/system/zdllnnn/zputdll
64-bit H-series and J-series OSS processes: /G/system/zdllnnn/yputdll
SYNOPSIS
[#include <cextdecs.h>]
#include <pthread.h>
short PUT_WRITEREADX(
short filenum,
char *buff er,
#ifdef __LP64
int write_count,
int read_count,
int *count_read,
#else
unsigned short write_count,
unsigned short read_count,
unsigned short *count_read,
#endif
long tag);
PARAMETERS
Input
filenum Specifies the file number of a Guardian file open instance that identifies the file
to be read.
write_count Specifies the number of bytes to be written.
read_count Specifies the number of bytes to be read.
tag (Optional) For nowait I/O only. The tag value you define uniquely identifies the
operation associated with this call.
This parameter is supported only for program compatibility; if you provide it, it
is ignored.
Output
buffer Specifies an array in the application process in which the information to be writ-
ten to the file is stored before the call. On return, buffer contains the information
read from the file.
count_read (Optional) For waited I/O only. This parameter returns a count of the number of
bytes returned from the file into buffer .
DESCRIPTION
The PUT_WRITEREADX() function is a thread-aware version of the Guardian
WRITEREADX procedure.
The PUT_WRITEREADX() function writes data to a file from an array in the application pro-
cess, then waits for data to be transferred back from the file. The data from the read portion
returns in the same array used for the write portion.
If the file is opened for nowait I/O, you must not modify the buffer before the I/O completes with
a call to the Guardian AWAITIOX procedure. This condition also applies to other processes that
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