Guardian C Library Calls Reference Manual

__ns_fopen_special (supplementary)
3-130 128833—Guardian TNS C Library Calls Reference Manual
Reference to Library Calls
•
For output streams, a call to a write function in user code might leave a partially
filled, unflushed buffer. To ensure that the buffer is flushed, you can:
•
Perform a flush operation, such as a call to the fflush function, prior to calling the
__ns_fget_file_state function.
•
Ignore the effects of unflushed buffers, if the unflushed buffer contents are not
critical to the application.
•
Disable buffering with the setvbuf or setnbuf function.
•
In addition to either the CLARGE or CWIDE library file, you must bind the
CNONSTOP library file into programs that use this function.
•
This function can only be used in the Guardian environment.
•
Refer to the Guardian Programmer’s Guide for complete details on fault-tolerant
programming in C.
__ns_fopen_special (supplementary)
The __ns_fopen_special function opens a file for ANSI-model I/O and allows a sync
depth to be specified.
file_name
points to a string containing a valid file name.
*access_mode
points to a string that specifies how you want to access the file. The possible values
for *access_mode are described under “Usage Guidelines.”
sync_depth
specifies the number of nonretryable write requests whose completion must be
remembered by the file system. sync_depth must conform to the operating system
limit of a value between zero and fifteen.
Return Value
points to the FILE structure denoting the opened file if the operation is successful;
otherwise, the function returns the pointer value NULL.
#include <nonstoph>
FILE *__ns_open_special(
char *file_name,
char *access_mode,
short sync_depth);