File: func_mmap_file.m4

package info (click to toggle)
llvm 2.2-12
  • links: PTS, VCS
  • area: main
  • in suites: lenny
  • size: 38,648 kB
  • ctags: 28,258
  • sloc: cpp: 215,479; sh: 12,132; ansic: 10,002; yacc: 5,525; perl: 2,352; ml: 1,580; makefile: 956; pascal: 718; lex: 602; exp: 320; ada: 193; lisp: 160; csh: 116; objc: 59; python: 59; tcl: 20
file content (26 lines) | stat: -rw-r--r-- 679 bytes parent folder | download | duplicates (22)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
#
# Check for the ability to mmap a file.  
#
AC_DEFUN([AC_FUNC_MMAP_FILE],
[AC_CACHE_CHECK(for mmap of files,
ac_cv_func_mmap_file,
[ AC_LANG_PUSH([C])
  AC_RUN_IFELSE([
    AC_LANG_PROGRAM([[
#include <sys/types.h>
#include <sys/mman.h>
#include <fcntl.h>
]],[[
  int fd;
  fd = creat ("foo",0777); 
  fd = (int) mmap (0, 1, PROT_READ, MAP_SHARED, fd, 0);
  unlink ("foo"); 
  return (fd != (int) MAP_FAILED);]])],
  [ac_cv_func_mmap_file=yes],[ac_cv_func_mmap_file=no],[ac_cv_func_mmap_file=no])
  AC_LANG_POP([C])
])
if test "$ac_cv_func_mmap_file" = yes; then
   AC_DEFINE([HAVE_MMAP_FILE],[],[Define if mmap() can map files into memory])
   AC_SUBST(MMAP_FILE,[yes])
fi
])