Guardian Native C Library Calls Reference Manual (G06.29+, H06.08+, J06.03+)

Guardian Native C Library Calls (f) fopen_guardian(3)
Explicit calls to the fopen_oss() and fopen_guardian() variants in source code are only made
when the behavior of one environment is desired from the other environment.
fopen_oss() is functionally identical to the fopen( ) function of the OSS environment. It is the
same as setting systype oss at compile-time. systype oss is the default setting for c89 in
the OSS environment and on UNIX workstations.
fopen_guardian() is functionally identical to the fopen() function of the Guardian environment.
It is the same as setting systype guardian at compile-time. systype guardian is the
default setting for the C and C++ compilers in the Guardian environment.
To use the fopen_oss( ) or fopen_guardian() functions, specify the _TANDEM_SOURCE
feature test macro.
RETURN VALUES
If the fopen() function succeeds, a pointer to the stream is returned. If the fopen() function fails,
a null pointer is returned, and errno is set to indicate the error.
ERRORS
If any of these conditions occurs, the fopen() function sets errno to the corresponding value.
[EINVAL] The mode parameter is not a valid mode.
[EMFILE] The OPEN_MAX file descriptors are currently open in the calling process.
[ENFILE] Too many files are currently open in the processor.
[ENOENT] The named file does not exist or the filename parameter points to an empty
string.
[ENOMEM] Insufficient space to allocate a buffer.
[EOVERFLOW]
The size of the file cannot be represented in an object of type off_t.
For all other error conditions, errno is set to the appropriate Guardian file-system error number.
Refer to the Guardian Procedure Errors and Messages Manual for more information about a
specific Guardian file-system error.
RELATED INFORMATION
Functions: open(2), fclose(3), fopen(3), fopen64_guardian(3), fopen_oss(3), freopen(3),
fseek(3), setbuf(3).
STANDARDS CONFORMANCE
The fopen_guardian() function is an HP extension to the XPG4 Version 2 specification.
527192-018 Hewlett-Packard Company 2−77