man pages section 3: Extended Library Functions, Volume 1

Tcl_SetErrno (3tcl)

Name

Tcl_SetErrno - 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)

Description

Tcl_SetErrno(3tcl)          Tcl Library Procedures          Tcl_SetErrno(3tcl)



______________________________________________________________________________

NAME
       Tcl_SetErrno,  Tcl_GetErrno,  Tcl_ErrnoId,  Tcl_ErrnoMsg  -  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)


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


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 bound-
       aries 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.


KEYWORDS
       errno, error code, global variables



ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | runtime/tcl-8    |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+

NOTES
       Source code for open source software components in Oracle  Solaris  can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-
       code-downloads.html.

       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source was downloaded from  http://prdownloads.sourceforge.net/tcl/tcl-
       core8.6.7-src.tar.gz.

       Further information about this software can be found on the open source
       community website at https://www.tcl.tk/.



Tcl                                   8.3                   Tcl_SetErrno(3tcl)