Path: utzoo!utgpu!watserv1!watmath!att!bu.edu!rpi!zaphod.mps.ohio-state.edu!wuarchive!bcm!lib!thesis1.hsch.utexas.edu
From: jmaynard@thesis1.hsch.utexas.edu (Jay Maynard)
Newsgroups: comp.sources.bugs
Subject: abc: syntax error in unix/u1file.c on System V
Message-ID: <4492@lib.tmc.edu>
Date: 21 Dec 90 22:04:53 GMT
Sender: usenet@lib.tmc.edu
Organization: University of Texas Medical School at Houston
Lines: 239
Nntp-Posting-Host: thesis1.hsch.utexas.edu
Originator: jmaynard@thesis1.hsch.utexas.edu


Problem: During compilation, file unix/u1file.c fails with a syntax error.

Environment: NCR Tower XP, System V release 2, OS release 3.02.01.

Description: The line in error is "extern char *getwd();". Under other than
AT&T System III/System V systems, this compiles as advertised. Under System
III/V, though, (any system that results in the ATT system type being selected
in Setup), this actually is compiled differently because of the line
"define getwd(path) getcwd(path, SIZE_BYTES)" in uhdrs/os.h - resulting in
the definition being turned into "extern char *getcwd(, SIZE_BYTES);". As
the compiler rightfully complains, this is a syntax error.

Fix: The following patch adds another definition to unix/os.h, for HAS_GETCWD;
adds logic in Setup to define it appropriately; changes unix/u1file.c to do
the right thing if it's set; and makes unix/u1os.c take it into account when
deciding whether or not to use its internal getwd() routine.
The patch may be applied by feeding this article to patch -p0.
---------------8<---------------cut here----------------->8-------------------
*** Setup.orig
--- Setup
**************
*** 686,691
  	perror="#define"
  	mkdir="#define"
  	getwd="#define"
  	rename="#define"
  	select="#define"
  	readdir="#define"
--- 686,692 -----
  	perror="#define"
  	mkdir="#define"
  	getwd="#define"
+ 	getcwd="#undef "
  	rename="#define"
  	select="#define"
  	readdir="#define"
**************
*** 695,700
  	perror="#define"
  	mkdir="#undef "
  	getwd="#undef "
  	rename="#undef "
  	select="#undef "
  	readdir="#undef "
--- 696,702 -----
  	perror="#define"
  	mkdir="#undef "
  	getwd="#undef "
+ 	getcwd="#undef "
  	rename="#undef "
  	select="#undef "
  	readdir="#undef "
**************
*** 704,709
  	perror="#define"
  	mkdir="#define"
  	getwd="#undef "
  	rename="#undef "
  	select="#undef "
  	readdir="#undef "
--- 706,712 -----
  	perror="#define"
  	mkdir="#define"
  	getwd="#undef "
+ 	getcwd="#define"
  	rename="#undef "
  	select="#undef "
  	readdir="#undef "
**************
*** 714,719
  	perror="#undef "
  	mkdir="#undef "
  	getwd="#undef "
  	rename="#undef "
  	select="#undef "
  	readdir="#undef "
--- 717,723 -----
  	perror="#undef "
  	mkdir="#undef "
  	getwd="#undef "
+ 	getcwd="#undef "
  	rename="#undef "
  	select="#undef "
  	readdir="#undef "
**************
*** 751,756
  /^#define HAS_PERROR/s?#define?$perror?
  /^#define HAS_MKDIR/s?#define?$mkdir?
  /^#define HAS_GETWD/s?#define?$getwd?
  /^#define HAS_RENAME/s?#define?$rename?
  /^#define HAS_SELECT/s?#define?$select?
  /^#define HAS_READDIR/s?#define?$readdir?
--- 755,761 -----
  /^#define HAS_PERROR/s?#define?$perror?
  /^#define HAS_MKDIR/s?#define?$mkdir?
  /^#define HAS_GETWD/s?#define?$getwd?
+ /^#define HAS_GETCWD/s?#define?$getcwd?
  /^#define HAS_RENAME/s?#define?$rename?
  /^#define HAS_SELECT/s?#define?$select?
  /^#define HAS_READDIR/s?#define?$readdir?
**************
*** 801,817
  case $strchr in
  strchr)	$editor uhdrs/os.h <<EOF
  /#define strchr/,/#define strrchr/d
- w
- q
- EOF
- ;;
- esac
- 
- case $unix in
- ATT)	$editor uhdrs/os.h <<EOF
- /#define HAS_GETWD/a
- #define getwd(path) getcwd(path, SIZE_PATH)
- .
  w
  q
  EOF
--- 806,811 -----
  case $strchr in
  strchr)	$editor uhdrs/os.h <<EOF
  /#define strchr/,/#define strrchr/d
  w
  q
  EOF
*** unix/u1file.c.orig
--- unix/u1file.c
**************
*** 6,11
  #include "bfil.h"
  
  extern char *getenv();
  extern char *getwd();
  
  Visible char *curdir() {
--- 6,14 -----
  #include "bfil.h"
  
  extern char *getenv();
+ #ifdef GETCWD
+ extern char *getcwd();
+ #else
  extern char *getwd();
  #endif
  
**************
*** 7,12
  
  extern char *getenv();
  extern char *getwd();
  
  Visible char *curdir() {
  	static char buffer[SIZE_PATH];
--- 10,16 -----
  extern char *getcwd();
  #else
  extern char *getwd();
+ #endif
  
  Visible char *curdir() {
  	static char buffer[SIZE_PATH];
**************
*** 10,15
  
  Visible char *curdir() {
  	static char buffer[SIZE_PATH];
  	return getwd(buffer);
  }
  
--- 14,22 -----
  
  Visible char *curdir() {
  	static char buffer[SIZE_PATH];
+ #ifdef GETCWD
+ 	return getcwd(buffer, SIZE_PATH);
+ #else
  	return getwd(buffer);
  #endif
  }
**************
*** 11,16
  Visible char *curdir() {
  	static char buffer[SIZE_PATH];
  	return getwd(buffer);
  }
  
  Hidden string searchfile(base, abclib) string base; string abclib; {
--- 18,24 -----
  	return getcwd(buffer, SIZE_PATH);
  #else
  	return getwd(buffer);
+ #endif
  }
  
  Hidden string searchfile(base, abclib) string base; string abclib; {
*** unix/u1os.c.orig
--- unix/u1os.c
**************
*** 16,21
  
  #endif /* !NDEBUG */
  
  #ifndef HAS_GETWD
  
  /* getwd - get working directory */
--- 16,24 -----
  
  #endif /* !NDEBUG */
  
+ #ifdef HAS_GETCWD
+ #define HAS_GETWD /* merge the two #defines */
+ #endif
  #ifndef HAS_GETWD
  
  /* getwd - get working directory */
*** uhdrs/os.h.gen.orig
--- uhdrs/os.h.gen
**************
*** 67,72
  #define HAS_PERROR	/* can use sys_errlist and sys_nerr (from perror(3)) */
  #define HAS_MKDIR	/* mkdir() and rmdir() available */
  #define HAS_GETWD	/* getwd() available */
  #define HAS_RENAME	/* rename() available */
  #define HAS_SELECT	/* 4.2 BSD select() system call available */
  #define HAS_READDIR	/* Berkeley style directory reading routines */
--- 67,73 -----
  #define HAS_PERROR	/* can use sys_errlist and sys_nerr (from perror(3)) */
  #define HAS_MKDIR	/* mkdir() and rmdir() available */
  #define HAS_GETWD	/* getwd() available */
+ #define HAS_GETCWD	/* getcwd() available? */
  #define HAS_RENAME	/* rename() available */
  #define HAS_SELECT	/* 4.2 BSD select() system call available */
  #define HAS_READDIR	/* Berkeley style directory reading routines */
-- 
Jay Maynard, EMT-P, K5ZC, PP-ASEL | Never ascribe to malice that which can
jmaynard@thesis1.hsch.utexas.edu  | adequately be explained by stupidity.
  "...flames are a specific art form of Usenet..." -- Gregory C. Woodbury