diff options
Diffstat (limited to 'lib/libc/gen/dlopen.3')
| -rw-r--r-- | lib/libc/gen/dlopen.3 | 36 |
1 files changed, 35 insertions, 1 deletions
diff --git a/lib/libc/gen/dlopen.3 b/lib/libc/gen/dlopen.3 index 3da9b6e..089e631 100644 --- a/lib/libc/gen/dlopen.3 +++ b/lib/libc/gen/dlopen.3 @@ -32,11 +32,12 @@ .\" @(#) dlopen.3 1.6 90/01/31 SMI .\" $FreeBSD$ .\" -.Dd July 7, 2009 +.Dd December 21, 2011 .Dt DLOPEN 3 .Os .Sh NAME .Nm dlopen , +.Nm fdlopen , .Nm dlsym , .Nm dlfunc , .Nm dlerror , @@ -49,6 +50,8 @@ .Ft void * .Fn dlopen "const char *path" "int mode" .Ft void * +.Fn fdlopen "int fd" "int mode" +.Ft void * .Fn dlsym "void * restrict handle" "const char * restrict symbol" .Ft dlfunc_t .Fn dlfunc "void * restrict handle" "const char * restrict symbol" @@ -164,6 +167,36 @@ be interrogated with .Fn dlerror . .Pp The +.Fn fdlopen +function is similar to +.Fn dlopen , +but it takes the file descriptor argument +.Fa fd , +which is used for the file operations needed to load an object +into the address space. +The file descriptor +.Fa fd +is not closed by the function regardless a result of execution, +but a duplicate of the file descriptor is. +This may be important if a +.Xr lockf 3 +lock is held on the passed descriptor. +The +.Fa fd +argument -1 is interpreted as a reference to the main +executable of the process, similar to +.Va NULL +value for the +.Fa name +argument to +.Fn dlopen . +The +.Fn fdlopen +function can be used by the code that needs to perform +additional checks on the loaded objects, to prevent races with +symlinking or renames. +.Pp +The .Fn dlsym function returns the address binding of the symbol described in the null-terminated @@ -354,6 +387,7 @@ option to the C language compiler. .Sh ERRORS The .Fn dlopen , +.Fn fdlopen , .Fn dlsym , and .Fn dlfunc |
