PR_GetSpecialFD
Gets the file descriptor that represents the standard input, output, or error stream.
Syntax
#include <prio.h>
PRFileDesc* PR_GetSpecialFD(PRSpecialFD id);
Parameter
The function has the following parameter:
id
A pointer to an enumerator of type
PRSpecialFD
, indicating the type of I/O stream desired:PR_StandardInput
,PR_StandardOutput
, orPR_StandardError
.
Returns
If the id
parameter is valid, PR_GetSpecialFD returns a file
descriptor that represents the corresponding standard I/O stream.
Otherwise, PR_GetSpecialFD returns NULL
and sets the error to
PR_INVALID_ARGUMENT_ERROR
.
Description
Type PRSpecialFD
is defined as follows:
typedef enum PRSpecialFD{
PR_StandardInput,
PR_StandardOutput,
PR_StandardError
} PRSpecialFD;
#define PR_STDIN PR_GetSpecialFD(PR_StandardInput)
#define PR_STDOUT PR_GetSpecialFD(PR_StandardOutput)
#define PR_STDERR PR_GetSpecialFD(PR_StandardError)
File descriptors returned by PR_GetSpecialFD are owned by the runtime and should not be closed by the caller.