Tcl_SetErrno, Tcl_GetErrno, Tcl_ErrnoId, Tcl_ErrnoMsg - manipulate errno to
store and retrieve error codes
#include <tcl.h>
void
Tcl_SetErrno(errorCode)
int
Tcl_GetErrno()
const char *
Tcl_ErrnoId()
const char *
Tcl_ErrnoMsg(errorCode)
- int errorCode (in)
- A POSIX error code such as ENOENT.
Tcl_SetErrno and
Tcl_GetErrno provide portable access to the
errno variable, which is used to record a POSIX error code after system
calls and other operations such as
Tcl_Gets. These procedures are
necessary because global variable accesses cannot be made across module
boundaries on some platforms.
Tcl_SetErrno sets the
errno variable to the value of the
errorCode argument C procedures that wish to return error information
to their callers via
errno should call
Tcl_SetErrno rather than
setting
errno directly.
Tcl_GetErrno returns the current value of
errno. Procedures
wishing to access
errno should call this procedure instead of accessing
errno directly.
Tcl_ErrnoId and
Tcl_ErrnoMsg return string representations of
errno values.
Tcl_ErrnoId returns a machine-readable textual
identifier such as “EACCES” that corresponds to the current
value of
errno.
Tcl_ErrnoMsg returns a human-readable string
such as “permission denied” that corresponds to the value of its
errorCode argument. The
errorCode argument is typically the
value returned by
Tcl_GetErrno. The strings returned by these functions
are statically allocated and the caller must not free or modify them.
errno, error code, global variables