16a17,43
> # Check environment variables CXX and COCOA_EXTLIB_DIR
> if [ -z "$CXX" ]
> then
>   echo "ERROR: $0: environment variable CXX not set."
>   exit 1
> fi
> 
> if [ -z "$COCOA_EXTLIB_DIR" ]
> then
>     echo "ERROR: $0: environment variable COCOA_EXTLIB_DIR not set."
>     exit 1
> fi
> 
> if [ \! "$COCOA_EXTLIB_DIR"  -ef "/$COCOA_EXTLIB_DIR" ]
> then
>   echo "ERROR: $0: environment variable COCOA_EXTLIB_DIR is not absolute: $COCOA_EXTLIB_DIR."
>   exit 1
> fi
> 
> if [ \! -d "$COCOA_EXTLIB_DIR" -o \! -d "$COCOA_EXTLIB_DIR/include" -o \! -d "$COCOA_EXTLIB_DIR/lib" ]
> then
>   echo "ERROR: $0: environment variable COCOA_EXTLIB_DIR is implausible: $COCOA_EXTLIB_DIR."
>   exit 1
> fi
> 
> 
> 
29,30c56,59
< TMP_DIR=gmp-check-cxxflags-$HOSTNAME-$$
< /bin/rm -rf $TMP_DIR && mkdir $TMP_DIR
---
> TODAY=`date "+%Y-%m-%d"`
> TIME=`date "+%H:%M:%S"`
> TMP_DIR=/tmp/CoCoALib-config-$USER-$TODAY/gmp-check-cxxflags-$TIME-$$
> /bin/rm -rf $TMP_DIR  &&  mkdir -p $TMP_DIR
53c82
< $CXX $CXXFLAGS $CXXFLAGS_FOR_GMP TestProg.c -o TestProg -I ../ExternalLibs/include -L../ExternalLibs/lib $GMP_LDLIB 2> /dev/null
---
> $CXX $CXXFLAGS $CXXFLAGS_FOR_GMP TestProg.c -o TestProg -I "$COCOA_EXTLIB_DIR/include" -L"$COCOA_EXTLIB_DIR/lib" $GMP_LDLIB 2> /dev/null
57a87
>   # Deliberately leave $TMP_DIR to assist debugging.
59,61c89
<   echo "ERROR: $CXX $CXXFLAGS $CXXFLAGS_FOR_GMP TestProg.c -o TestProg -I ../ExternalLibs/include -L../ExternalLibs/lib $GMP_LDLIB"
< #  cd ..
< #  /bin/rm -rf $TMP_DIR
---
>   echo "ERROR: $CXX $CXXFLAGS $CXXFLAGS_FOR_GMP TestProg.c -o TestProg -I \"$COCOA_EXTLIB_DIR/include\" -L\"$COCOA_EXTLIB_DIR/lib\" $GMP_LDLIB"
71,73c99,100
<   echo "ERROR: $0 TestProg crashed"
< #  cd ..
< #  /bin/rm -rf $TMP_DIR
---
>   # Deliberately leave $TMP_DIR to assist debugging.
>   echo "ERROR: $0: TestProg crashed (probably linker problem for libgmp)"
77c104,105
< cd ..
---
> # Clean up TMP_DIR
> cd # Leave TMP_DIR