diff options
Diffstat (limited to 'hurd/porting/guidelines.mdwn')
| -rw-r--r-- | hurd/porting/guidelines.mdwn | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/hurd/porting/guidelines.mdwn b/hurd/porting/guidelines.mdwn index 03ce9e19..e47d4408 100644 --- a/hurd/porting/guidelines.mdwn +++ b/hurd/porting/guidelines.mdwn @@ -1,5 +1,5 @@ -[[!meta copyright="Copyright © 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011 -Free Software Foundation, Inc."]] +[[!meta copyright="Copyright © 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011, +2012 Free Software Foundation, Inc."]] [[!meta license="""[[!toggle id="license" text="GFDL 1.2+"]][[!toggleable id="license" text="Permission is granted to copy, distribute and/or modify this @@ -112,6 +112,8 @@ If you get Bad File Descriptor error when trying to read from a file (or accessi ## <a name="PATH_MAX_tt_MAX_PATH_tt_MAXPATHL">`PATH_MAX`, `MAX_PATH`, `MAXPATHLEN`, `_POSIX_PATH_MAX`</a> +<http://pubs.opengroup.org/onlinepubs/009695399/basedefs/limits.h.html> + Every unconditionalized use of `PATH_MAX`, `MAX_PATH` or `MAXPATHLEN` is a POSIX incompatibility. If there is no upper limit on the length of a path (as its the case for GNU), this symbol is not defined in any header file. Instead, you need to either use a different implementation that does not rely on the length of a string or use `sysconf()` to query the length at runtime. If `sysconf()` returns -1, you have to use `realloc()` to allocate the needed memory dynamically. Usually it is thus simpler to just use dynamic allocation. Sometimes the amount is actually known. Else, a geometrically growing loop can be used: for instance, see [Alioth patch](http://alioth.debian.org/tracker/download.php/30628/410472/303735/1575/cpulimit-path-max-fix.patch) or [Pulseaudio patch](http://bugs.debian.org/cgi-bin/bugreport.cgi?msg=5;filename=patch-pulse;att=1;bug=522100). Note that in some cases there are GNU extensions that just work fine: when the `__GLIBC__` macro is defined, `getcwd()` calls can be just replaced by `get_current_dir_name()` calls. Note: constants such as `_POSIX_PATH_MAX` are only the minimum required value |