HP SunSoft Pascal 4.0 manual Commands to compile and execute StrVar.c, 120

6

The commands to compile and execute StrVar.c and

StrVarMain.p

hostname% cc -c StrVar.c hostname% pc StrVar.o StrVarMain.p

hostname% a.out abcdefghij abcdefghijklmnopqrtstuvwxyz varstr

length(v) = 6

Incorrect use of string in static variable storage

Avoid constructs that rely on strings being in static variable storage. For example, you could use mktemp(3) in Pascal as follows:

tmp := mktemp('/tmp/eph.xxxxxx')

Correct solution using the C library routine strncpy()

This use is incorrect, since mktemp()modifies its argument. Instead, use the C library routine strncpy() (see string(3)) to copy the string constant to a declared char array variable, as in:

program Use_mktemp ;

procedure strncpy( var dest: univ string ; var srce: univ string ;

length: integer) ; external c ;

procedure mktemp(var dest: univ string); external c;

...

var path: string ; begin

...

strncpy( path, '/tmp/eph.xxxxxx', sizeof(path)) ; mktemp( path ) ;

...

end .

120 Pascal 4.0 User’s Guide