NAME

       Tcl_SetErrno,  Tcl_GetErrno,  Tcl_ErrnoId,  Tcl_ErrnoMsg, Tcl_WinConvertError - manipulate errno to store
       and retrieve error codes

SYNOPSIS

       #include <tcl.h>

       void
       Tcl_SetErrno(errorCode)

       int
       Tcl_GetErrno()

       const char *
       Tcl_ErrnoId()

       const char *
       Tcl_ErrnoMsg(errorCode)

       void
       Tcl_WinConvertError(winErrorCode)

ARGUMENTS

       int errorCode (in)          A POSIX error code such as ENOENT.

       DWORD winErrorCode (in)    A Windows or Winsock error code such as ERROR_FILE_NOT_FOUND.
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DESCRIPTION

       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.

       Tcl_WinConvertError (Windows only) maps the passed Windows or Winsock error code to  a  POSIX  error  and
       stores it in errno.

KEYWORDS

       errno, error code, global variables

Tcl                                                    8.3                                    Tcl_SetErrno(3tcl)