Rename mch_* functions to os_* in os module.

38 files changed, 220 insertions, 220 deletions

diff --git a/src/buffer.c b/src/buffer.c
index d0d0b033df..d3c26956b3 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -2425,7 +2425,7 @@ void buflist_altfpos(win_T *win)
 
 /*
  * Return TRUE if 'ffname' is not the same file as current file.
- * Fname must have a full path (expanded by mch_get_absolute_path()).
+ * Fname must have a full path (expanded by os_get_absolute_path()).
  */
 int otherfile(char_u *ffname)
 {
diff --git a/src/diff.c b/src/diff.c
index 0764715685..35b8e2e346 100644
--- a/src/diff.c
+++ b/src/diff.c
@@ -824,7 +824,7 @@ static void diff_file(char_u *tmp_orig, char_u *tmp_new, char_u *tmp_diff)
 
     if (cmd != NULL) {
       /* We don't want $DIFF_OPTIONS to get in the way. */
-      if (mch_getenv("DIFF_OPTIONS")) {
+      if (os_getenv("DIFF_OPTIONS")) {
         vim_setenv((char_u *)"DIFF_OPTIONS", (char_u *)"");
       }
 
@@ -906,18 +906,18 @@ void ex_diffpatch(exarg_T *eap)
   // have our own temp dir use that instead, it will be cleaned up when we
   // exit (any .rej files created).  Don't change directory if we can't
   // return to the current.
-  if ((mch_dirname(dirbuf, MAXPATHL) != OK)
-      || (mch_chdir((char *)dirbuf) != 0)) {
+  if ((os_dirname(dirbuf, MAXPATHL) != OK)
+      || (os_chdir((char *)dirbuf) != 0)) {
     dirbuf[0] = NUL;
   } else {
 # ifdef TEMPDIRNAMES
     if (vim_tempdir != NULL) {
-      ignored = mch_chdir((char *)vim_tempdir);
+      ignored = os_chdir((char *)vim_tempdir);
     } else {
-      ignored = mch_chdir("/tmp");
+      ignored = os_chdir("/tmp");
     }
 # else
-    ignored = mch_chdir("/tmp");
+    ignored = os_chdir("/tmp");
 # endif  // ifdef TEMPDIRNAMES
     shorten_fnames(TRUE);
   }
@@ -948,7 +948,7 @@ void ex_diffpatch(exarg_T *eap)
 
 #ifdef UNIX
   if (dirbuf[0] != NUL) {
-    if (mch_chdir((char *)dirbuf) != 0) {
+    if (os_chdir((char *)dirbuf) != 0) {
       EMSG(_(e_prev_dir));
     }
     shorten_fnames(TRUE);
diff --git a/src/eval.c b/src/eval.c
index df097d5e37..1e2cbfc39d 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -8549,7 +8549,7 @@ static void f_eventhandler(typval_T *argvars, typval_T *rettv)
  */
 static void f_executable(typval_T *argvars, typval_T *rettv)
 {
-  rettv->vval.v_number = mch_can_exe(get_tv_string(&argvars[0]));
+  rettv->vval.v_number = os_can_exe(get_tv_string(&argvars[0]));
 }
 
 /*
@@ -8565,7 +8565,7 @@ static void f_exists(typval_T *argvars, typval_T *rettv)
   p = get_tv_string(&argvars[0]);
   if (*p == '$') {                      /* environment variable */
     /* first try "normal" environment variables (fast) */
-    if (mch_getenv((char *)(p + 1)) != NULL)
+    if (os_getenv((char *)(p + 1)) != NULL)
       n = TRUE;
     else {
       /* try expanding things like $VIM and ${HOME} */
@@ -8862,7 +8862,7 @@ static void f_filereadable(typval_T *argvars, typval_T *rettv)
 # define O_NONBLOCK 0
 #endif
   p = get_tv_string(&argvars[0]);
-  if (*p && !mch_isdir(p) && (fd = mch_open((char *)p,
+  if (*p && !os_isdir(p) && (fd = mch_open((char *)p,
                                   O_RDONLY | O_NONBLOCK, 0)) >= 0) {
     n = TRUE;
     close(fd);
@@ -9660,7 +9660,7 @@ static void f_getcwd(typval_T *argvars, typval_T *rettv)
   rettv->vval.v_string = NULL;
   cwd = alloc(MAXPATHL);
   if (cwd != NULL) {
-    if (mch_dirname(cwd, MAXPATHL) != FAIL) {
+    if (os_dirname(cwd, MAXPATHL) != FAIL) {
       rettv->vval.v_string = vim_strsave(cwd);
 #ifdef BACKSLASH_IN_FILENAME
       if (rettv->vval.v_string != NULL)
@@ -9719,7 +9719,7 @@ static void f_getfsize(typval_T *argvars, typval_T *rettv)
   rettv->v_type = VAR_NUMBER;
 
   if (mch_stat((char *)fname, &st) >= 0) {
-    if (mch_isdir(fname))
+    if (os_isdir(fname))
       rettv->vval.v_number = 0;
     else {
       rettv->vval.v_number = (varnumber_T)st.st_size;
@@ -9812,7 +9812,7 @@ static void f_getftype(typval_T *argvars, typval_T *rettv)
     default: t = "other";
     }
 # else
-    if (mch_isdir(fname))
+    if (os_isdir(fname))
       t = "dir";
     else
       t = "file";
@@ -10886,7 +10886,7 @@ static void f_invert(typval_T *argvars, typval_T *rettv)
  */
 static void f_isdirectory(typval_T *argvars, typval_T *rettv)
 {
-  rettv->vval.v_number = mch_isdir(get_tv_string(&argvars[0]));
+  rettv->vval.v_number = os_isdir(get_tv_string(&argvars[0]));
 }
 
 /*
@@ -11664,7 +11664,7 @@ static int mkdir_recurse(char_u *dir, int prot)
   updir = vim_strnsave(dir, (int)(p - dir));
   if (updir == NULL)
     return FAIL;
-  if (mch_isdir(updir))
+  if (os_isdir(updir))
     r = OK;
   else if (mkdir_recurse(updir, prot) == OK)
     r = vim_mkdir_emsg(updir, prot);
@@ -12479,7 +12479,7 @@ static void f_resolve(typval_T *argvars, typval_T *rettv)
           q[-1] = NUL;
           q = gettail(p);
         }
-        if (q > p && !mch_is_absolute_path(buf)) {
+        if (q > p && !os_is_absolute_path(buf)) {
           /* symlink is relative to directory of argument */
           cpy = alloc((unsigned)(STRLEN(p) + STRLEN(buf) + 1));
           if (cpy != NULL) {
@@ -19345,7 +19345,7 @@ repeat:
     }
 
     /* Append a path separator to a directory. */
-    if (mch_isdir(*fnamep)) {
+    if (os_isdir(*fnamep)) {
       /* Make room for one or two extra characters. */
       *fnamep = vim_strnsave(*fnamep, (int)STRLEN(*fnamep) + 2);
       vim_free(*bufp);          /* free any allocated file name */
@@ -19379,7 +19379,7 @@ repeat:
 
     if (p != NULL) {
       if (c == '.') {
-        mch_dirname(dirname, MAXPATHL);
+        os_dirname(dirname, MAXPATHL);
         s = shorten_fname(p, dirname);
         if (s != NULL) {
           *fnamep = s;
diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index d0e4c9eccd..15429e5b7d 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -1730,7 +1730,7 @@ static char_u *viminfo_filename(char_u *file)
     else if ((file = find_viminfo_parameter('n')) == NULL || *file == NUL) {
 #ifdef VIMINFO_FILE2
       /* don't use $HOME when not defined (turned into "c:/"!). */
-      if (mch_getenv((char_u *)"HOME") == NULL) {
+      if (os_getenv((char_u *)"HOME") == NULL) {
         /* don't use $VIM when not available. */
         expand_env((char_u *)"$VIM", NameBuff, MAXPATHL);
         if (STRCMP("$VIM", NameBuff) != 0)          /* $VIM was expanded */
@@ -2335,7 +2335,7 @@ check_overwrite (
     if (!eap->forceit && !eap->append) {
 #ifdef UNIX
       /* with UNIX it is possible to open a directory */
-      if (mch_isdir(ffname)) {
+      if (os_isdir(ffname)) {
         EMSG2(_(e_isadir2), ffname);
         return FAIL;
       }
@@ -5384,7 +5384,7 @@ void ex_helptags(exarg_T *eap)
   xpc.xp_context = EXPAND_DIRECTORIES;
   dirname = ExpandOne(&xpc, eap->arg, NULL,
       WILD_LIST_NOTFOUND|WILD_SILENT, WILD_EXPAND_FREE);
-  if (dirname == NULL || !mch_isdir(dirname)) {
+  if (dirname == NULL || !os_isdir(dirname)) {
     EMSG2(_("E150: Not a directory: %s"), eap->arg);
     return;
   }
diff --git a/src/ex_cmds2.c b/src/ex_cmds2.c
index b461f8392a..004e0e5061 100644
--- a/src/ex_cmds2.c
+++ b/src/ex_cmds2.c
@@ -2493,7 +2493,7 @@ do_source (
   vim_free(p);
   if (fname_exp == NULL)
     return retval;
-  if (mch_isdir(fname_exp)) {
+  if (os_isdir(fname_exp)) {
     smsg((char_u *)_("Cannot source a directory: \"%s\""), fname);
     goto theend;
   }
@@ -3317,11 +3317,11 @@ char_u *get_mess_lang(void)
   p = (char_u *)get_locale_val(LC_COLLATE);
 #  endif
 # else
-  p = mch_getenv((char_u *)"LC_ALL");
+  p = os_getenv((char_u *)"LC_ALL");
   if (p == NULL || *p == NUL) {
-    p = mch_getenv((char_u *)"LC_MESSAGES");
+    p = os_getenv((char_u *)"LC_MESSAGES");
     if (p == NULL || *p == NUL)
-      p = mch_getenv((char_u *)"LANG");
+      p = os_getenv((char_u *)"LANG");
   }
 # endif
   return p;
@@ -3338,11 +3338,11 @@ static char_u *get_mess_env(void)
 {
   char_u      *p;
 
-  p = (char_u *)mch_getenv("LC_ALL");
+  p = (char_u *)os_getenv("LC_ALL");
   if (p == NULL || *p == NUL) {
-    p = (char_u *)mch_getenv("LC_MESSAGES");
+    p = (char_u *)os_getenv("LC_MESSAGES");
     if (p == NULL || *p == NUL) {
-      p = (char_u *)mch_getenv("LANG");
+      p = (char_u *)os_getenv("LANG");
       if (p != NULL && VIM_ISDIGIT(*p))
         p = NULL;                       /* ignore something like "1043" */
 # ifdef HAVE_GET_LOCALE_VAL
diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index d16458fe2d..01da8f6fff 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -6607,7 +6607,7 @@ void post_chdir(int local)
     if (globaldir == NULL && prev_dir != NULL)
       globaldir = vim_strsave(prev_dir);
     /* Remember this local directory for the window. */
-    if (mch_dirname(NameBuff, MAXPATHL) == OK)
+    if (os_dirname(NameBuff, MAXPATHL) == OK)
       curwin->w_localdir = vim_strsave(NameBuff);
   } else {
     /* We are now in the global directory, no need to remember its
@@ -6656,7 +6656,7 @@ void ex_cd(exarg_T *eap)
 
     /* Save current directory for next ":cd -" */
     tofree = prev_dir;
-    if (mch_dirname(NameBuff, MAXPATHL) == OK)
+    if (os_dirname(NameBuff, MAXPATHL) == OK)
       prev_dir = vim_strsave(NameBuff);
     else
       prev_dir = NULL;
@@ -6687,7 +6687,7 @@ void ex_cd(exarg_T *eap)
  */
 static void ex_pwd(exarg_T *eap)
 {
-  if (mch_dirname(NameBuff, MAXPATHL) == OK) {
+  if (os_dirname(NameBuff, MAXPATHL) == OK) {
 #ifdef BACKSLASH_IN_FILENAME
     slash_adjust(NameBuff);
 #endif
@@ -7281,7 +7281,7 @@ static void ex_mkrc(exarg_T *eap)
 
 #if defined(FEAT_SESSION) && defined(vim_mkdir)
   /* When using 'viewdir' may have to create the directory. */
-  if (using_vdir && !mch_isdir(p_vdir))
+  if (using_vdir && !os_isdir(p_vdir))
     vim_mkdir_emsg(p_vdir, 0755);
 #endif
 
@@ -7337,15 +7337,15 @@ static void ex_mkrc(exarg_T *eap)
           /*
            * Change to session file's dir.
            */
-          if (mch_dirname(dirnow, MAXPATHL) == FAIL
-              || mch_chdir((char *)dirnow) != 0)
+          if (os_dirname(dirnow, MAXPATHL) == FAIL
+              || os_chdir((char *)dirnow) != 0)
             *dirnow = NUL;
           if (*dirnow != NUL && (ssop_flags & SSOP_SESDIR)) {
             if (vim_chdirfile(fname) == OK)
               shorten_fnames(TRUE);
           } else if (*dirnow != NUL
                      && (ssop_flags & SSOP_CURDIR) && globaldir != NULL) {
-            if (mch_chdir((char *)globaldir) == 0)
+            if (os_chdir((char *)globaldir) == 0)
               shorten_fnames(TRUE);
           }
 
@@ -7355,7 +7355,7 @@ static void ex_mkrc(exarg_T *eap)
           if (*dirnow != NUL && ((ssop_flags & SSOP_SESDIR)
                                  || ((ssop_flags & SSOP_CURDIR) && globaldir !=
                                      NULL))) {
-            if (mch_chdir((char *)dirnow) != 0)
+            if (os_chdir((char *)dirnow) != 0)
               EMSG(_(e_prev_dir));
             shorten_fnames(TRUE);
           }
@@ -7428,7 +7428,7 @@ open_exfile (
 
 #ifdef UNIX
   /* with Unix it is possible to open a directory */
-  if (mch_isdir(fname)) {
+  if (os_isdir(fname)) {
     EMSG2(_(e_isadir2), fname);
     return NULL;
   }
diff --git a/src/ex_getln.c b/src/ex_getln.c
index e0fc7ec28f..b979373ead 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -3256,13 +3256,13 @@ static int showmatches(expand_T *xp, int wildmenu)
             exp_path = expand_env_save_opt(files_found[k], TRUE);
             halved_slash = backslash_halve_save(
                 exp_path != NULL ? exp_path : files_found[k]);
-            j = mch_isdir(halved_slash != NULL ? halved_slash
+            j = os_isdir(halved_slash != NULL ? halved_slash
                 : files_found[k]);
             vim_free(exp_path);
             vim_free(halved_slash);
           } else
             /* Expansion was done here, file names are literal. */
-            j = mch_isdir(files_found[k]);
+            j = os_isdir(files_found[k]);
           if (showtail)
             p = L_SHOWFILE(k);
           else {
@@ -3954,7 +3954,7 @@ expand_shellcmd (
   flags |= EW_FILE | EW_EXEC;
 
   /* For an absolute name we don't use $PATH. */
-  if (mch_is_absolute_path(pat))
+  if (os_is_absolute_path(pat))
     path = (char_u *)" ";
   else if ((pat[0] == '.' && (vim_ispathsep(pat[1])
                               || (pat[1] == '.' && vim_ispathsep(pat[2])))))
diff --git a/src/file_search.c b/src/file_search.c
index 92f2a9b509..a7c8b1bf46 100644
--- a/src/file_search.c
+++ b/src/file_search.c
@@ -343,7 +343,7 @@ vim_findfile_init (
       path += 2;
     } else
 #endif
-    if (mch_dirname(ff_expand_buffer, MAXPATHL) == FAIL)
+    if (os_dirname(ff_expand_buffer, MAXPATHL) == FAIL)
       goto error_return;
 
     search_ctx->ffsc_start_dir = vim_strsave(ff_expand_buffer);
@@ -498,7 +498,7 @@ vim_findfile_init (
 
     STRCPY(buf, ff_expand_buffer);
     STRCPY(buf + eb_len, search_ctx->ffsc_fix_path);
-    if (mch_isdir(buf)) {
+    if (os_isdir(buf)) {
       STRCAT(ff_expand_buffer, search_ctx->ffsc_fix_path);
       add_pathsep(ff_expand_buffer);
     } else {
@@ -818,7 +818,7 @@ char_u *vim_findfile(void *search_ctx_arg)
           for (i = stackp->ffs_filearray_cur;
                i < stackp->ffs_filearray_size; ++i) {
             if (!path_with_url(stackp->ffs_filearray[i])
-                && !mch_isdir(stackp->ffs_filearray[i]))
+                && !os_isdir(stackp->ffs_filearray[i]))
               continue;                 /* not a directory */
 
             /* prepare the filename to be checked for existence
@@ -844,7 +844,7 @@ char_u *vim_findfile(void *search_ctx_arg)
                            == FINDFILE_BOTH
                            || ((search_ctx->ffsc_find_what
                                 == FINDFILE_DIR)
-                               == mch_isdir(file_path)))))
+                               == os_isdir(file_path)))))
 #ifndef FF_VERBOSE
                   && (ff_check_visited(
                           &search_ctx->ffsc_visited_list->ffvl_visited_list,
@@ -877,7 +877,7 @@ char_u *vim_findfile(void *search_ctx_arg)
 
                 if (!path_with_url(file_path))
                   simplify_filename(file_path);
-                if (mch_dirname(ff_expand_buffer, MAXPATHL)
+                if (os_dirname(ff_expand_buffer, MAXPATHL)
                     == OK) {
                   p = shorten_fname(file_path,
                       ff_expand_buffer);
@@ -910,7 +910,7 @@ char_u *vim_findfile(void *search_ctx_arg)
            */
           for (i = stackp->ffs_filearray_cur;
                i < stackp->ffs_filearray_size; ++i) {
-            if (!mch_isdir(stackp->ffs_filearray[i]))
+            if (!os_isdir(stackp->ffs_filearray[i]))
               continue;                 /* not a directory */
 
             ff_push(search_ctx,
@@ -934,7 +934,7 @@ char_u *vim_findfile(void *search_ctx_arg)
           if (fnamecmp(stackp->ffs_filearray[i],
                   stackp->ffs_fix_path) == 0)
             continue;             /* don't repush same directory */
-          if (!mch_isdir(stackp->ffs_filearray[i]))
+          if (!os_isdir(stackp->ffs_filearray[i]))
             continue;               /* not a directory */
           ff_push(search_ctx,
               ff_create_stack_element(stackp->ffs_filearray[i],
@@ -1519,7 +1519,7 @@ find_file_in_path_option (
             (os_file_exists(NameBuff)
              && (find_what == FINDFILE_BOTH
                  || ((find_what == FINDFILE_DIR)
-                     == mch_isdir(NameBuff))))) {
+                     == os_isdir(NameBuff))))) {
             file_name = vim_strsave(NameBuff);
             goto theend;
           }
diff --git a/src/fileio.c b/src/fileio.c
index 2cf4e15aeb..3f639ac59f 100644
--- a/src/fileio.c
+++ b/src/fileio.c
@@ -405,7 +405,7 @@ readfile (
      * On Unix it is possible to read a directory, so we have to
      * check for it before the mch_open().
      */
-    perm = mch_getperm(fname);
+    perm = os_getperm(fname);
     if (perm >= 0 && !S_ISREG(perm)                 /* not a regular file ... */
 # ifdef S_ISFIFO
         && !S_ISFIFO(perm)                          /* ... or fifo */
@@ -508,8 +508,8 @@ readfile (
     /*
      * On MSDOS and Amiga we can't open a directory, check here.
      */
-    isdir_f = (mch_isdir(fname));
-    perm = mch_getperm(fname);      /* check if the file exists */
+    isdir_f = (os_isdir(fname));
+    perm = os_getperm(fname);      /* check if the file exists */
     if (isdir_f) {
       filemess(curbuf, sfname, (char_u *)_("is a directory"), 0);
       curbuf->b_p_ro = TRUE;            /* must use "w!" now */
@@ -613,7 +613,7 @@ readfile (
     /* Set swap file protection bits after creating it. */
     if (swap_mode > 0 && curbuf->b_ml.ml_mfp != NULL
         && curbuf->b_ml.ml_mfp->mf_fname != NULL)
-      (void)mch_setperm(curbuf->b_ml.ml_mfp->mf_fname, (long)swap_mode);
+      (void)os_setperm(curbuf->b_ml.ml_mfp->mf_fname, (long)swap_mode);
 #endif
   }
 
@@ -2879,10 +2879,10 @@ buf_write (
     newfile = TRUE;
     perm = -1;
   } else {
-    perm = mch_getperm(fname);
+    perm = os_getperm(fname);
     if (perm < 0)
       newfile = TRUE;
-    else if (mch_isdir(fname)) {
+    else if (os_isdir(fname)) {
       errnum = (char_u *)"E502: ";
       errmsg = (char_u *)_("is a directory");
       goto fail;
@@ -3201,7 +3201,7 @@ buf_write (
           } else {
             /* set file protection same as original file, but
              * strip s-bit */
-            (void)mch_setperm(backup, perm & 0777);
+            (void)os_setperm(backup, perm & 0777);
 
 #ifdef UNIX
             /*
@@ -3215,7 +3215,7 @@ buf_write (
                 && fchown(bfd, (uid_t)-1, st_old.st_gid) != 0
 # endif
                 )
-              mch_setperm(backup,
+              os_setperm(backup,
                   (perm & 0707) | ((perm & 07) << 3));
 # ifdef HAVE_SELINUX
             mch_copy_sec(fname, backup);
@@ -3371,7 +3371,7 @@ nobackup:
   if (forceit && perm >= 0 && !(perm & 0200) && st_old.st_uid == getuid()
       && vim_strchr(p_cpo, CPO_FWRITE) == NULL) {
     perm |= 0200;
-    (void)mch_setperm(fname, perm);
+    (void)os_setperm(fname, perm);
     made_writable = TRUE;
   }
 #endif
@@ -3760,7 +3760,7 @@ restore_backup:
         || st.st_gid != st_old.st_gid) {
       ignored = fchown(fd, st_old.st_uid, st_old.st_gid);
       if (perm >= 0)            /* set permission again, may have changed */
-        (void)mch_setperm(wfname, perm);
+        (void)os_setperm(wfname, perm);
     }
 # endif
     buf_setino(buf);
@@ -3779,7 +3779,7 @@ restore_backup:
     perm &= ~0200;              /* reset 'w' bit for security reasons */
 #endif
   if (perm >= 0)                /* set perm. of new file same as old file */
-    (void)mch_setperm(wfname, perm);
+    (void)os_setperm(wfname, perm);
 #ifdef HAVE_ACL
   /* Probably need to set the ACL before changing the user (can't set the
    * ACL on a file the user doesn't own). */
@@ -3996,7 +3996,7 @@ restore_backup:
         close(empty_fd);
     }
     if (org != NULL) {
-      mch_setperm((char_u *)org, mch_getperm(fname) & 0777);
+      os_setperm((char_u *)org, os_getperm(fname) & 0777);
       vim_free(org);
     }
   }
@@ -4716,7 +4716,7 @@ char_u *shorten_fname1(char_u *full_path)
   dirname = alloc(MAXPATHL);
   if (dirname == NULL)
     return full_path;
-  if (mch_dirname(dirname, MAXPATHL) == OK) {
+  if (os_dirname(dirname, MAXPATHL) == OK) {
     p = shorten_fname(full_path, dirname);
     if (p == NULL || *p == NUL)
       p = full_path;
@@ -4768,14 +4768,14 @@ void shorten_fnames(int force)
   buf_T       *buf;
   char_u      *p;
 
-  mch_dirname(dirname, MAXPATHL);
+  os_dirname(dirname, MAXPATHL);
   for (buf = firstbuf; buf != NULL; buf = buf->b_next) {
     if (buf->b_fname != NULL
         && !bt_nofile(buf)
         && !path_with_url(buf->b_fname)
         && (force
             || buf->b_sfname == NULL
-            || mch_is_absolute_path(buf->b_sfname))) {
+            || os_is_absolute_path(buf->b_sfname))) {
       vim_free(buf->b_sfname);
       buf->b_sfname = NULL;
       p = shorten_fname(buf->b_ffname, dirname);
@@ -4810,7 +4810,7 @@ void shorten_filenames(char_u **fnames, int count)
 
   if (fnames == NULL || count < 1)
     return;
-  mch_dirname(dirname, sizeof(dirname));
+  os_dirname(dirname, sizeof(dirname));
   for (i = 0; i < count; ++i) {
     if ((p = shorten_fname(fnames[i], dirname)) != NULL) {
       /* shorten_fname() returns pointer in given "fnames[i]".  If free
@@ -4875,7 +4875,7 @@ buf_modname (
     retval = alloc((unsigned)(MAXPATHL + extlen + 3));
     if (retval == NULL)
       return NULL;
-    if (mch_dirname(retval, MAXPATHL) == FAIL ||
+    if (os_dirname(retval, MAXPATHL) == FAIL ||
         (fnamelen = (int)STRLEN(retval)) == 0) {
       vim_free(retval);
       return NULL;
@@ -5185,7 +5185,7 @@ int vim_rename(char_u *from, char_u *to)
   /*
    * Rename() failed, try copying the file.
    */
-  perm = mch_getperm(from);
+  perm = os_getperm(from);
 #ifdef HAVE_ACL
   /* For systems that support ACL: get the ACL from the original file. */
   acl = mch_get_acl(from);
@@ -5234,7 +5234,7 @@ int vim_rename(char_u *from, char_u *to)
     to = from;
   }
 #ifndef UNIX        /* for Unix mch_open() already set the permission */
-  mch_setperm(to, perm);
+  os_setperm(to, perm);
 #endif
 #ifdef HAVE_ACL
   mch_set_acl(to, acl);
@@ -5405,7 +5405,7 @@ buf_check_timestamp (
 #ifdef HAVE_ST_MODE
                  || (int)st.st_mode != buf->b_orig_mode
 #else
-                 || mch_getperm(buf->b_ffname) != buf->b_orig_mode
+                 || os_getperm(buf->b_ffname) != buf->b_orig_mode
 #endif
                  )) {
     retval = 1;
@@ -5421,7 +5421,7 @@ buf_check_timestamp (
 
     /* Don't do anything for a directory.  Might contain the file
      * explorer. */
-    if (mch_isdir(buf->b_fname))
+    if (os_isdir(buf->b_fname))
       ;
 
     /*
@@ -5725,7 +5725,7 @@ void buf_store_time(buf_T *buf, struct stat *st, char_u *fname)
 #ifdef HAVE_ST_MODE
   buf->b_orig_mode = (int)st->st_mode;
 #else
-  buf->b_orig_mode = mch_getperm(fname);
+  buf->b_orig_mode = os_getperm(fname);
 #endif
 }
 
@@ -5836,7 +5836,7 @@ vim_tempname (
 
       /* expand $TMP, leave room for "/v1100000/999999999" */
       expand_env((char_u *)tempdirs[i], itmp, TEMPNAMELEN - 20);
-      if (mch_isdir(itmp)) {                    /* directory exists */
+      if (os_isdir(itmp)) {                    /* directory exists */
         add_pathsep(itmp);
 
 # ifdef HAVE_MKDTEMP
diff --git a/src/globals.h b/src/globals.h
index 960e828532..56d2a24235 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -1137,6 +1137,6 @@ EXTERN char *ignoredp;
  * os_unix.c */
 EXTERN int curr_tmode INIT(= TMODE_COOK); /* contains current terminal mode */
 /* volatile because it is used in signal handler deathtrap(). */
-EXTERN volatile bool in_mch_delay INIT(= false);  /* sleeping in mch_delay() */
+EXTERN volatile bool in_os_delay INIT(= false);  /* sleeping in os_delay() */
 
 #endif /* NEOVIM_GLOBALS_H */
diff --git a/src/hardcopy.c b/src/hardcopy.c
index 0b5d29e998..239e1bd0ac 100644
--- a/src/hardcopy.c
+++ b/src/hardcopy.c
@@ -2534,7 +2534,7 @@ int mch_print_begin(prt_settings_T *psettings)
    */
   prt_dsc_start();
   prt_dsc_textline("Title", (char *)psettings->jobname);
-  if (mch_get_user_name(buffer, 256) == FAIL) {
+  if (os_get_user_name(buffer, 256) == FAIL) {
     STRCPY(buffer, "Unknown");
   }
   prt_dsc_textline("For", buffer);
diff --git a/src/if_cscope.c b/src/if_cscope.c
index 85633db927..fc7864b6e8 100644
--- a/src/if_cscope.c
+++ b/src/if_cscope.c
@@ -2073,7 +2073,7 @@ static void cs_release_csp(int i, int freefnpp)
       waitpid_errno = errno;
       if (pid != 0)
         break;          /* break unless the process is still running */
-      mch_delay(50L, FALSE);       /* sleep 50 ms */
+      os_delay(50L, FALSE);       /* sleep 50 ms */
     }
 # endif
     /*
@@ -2104,7 +2104,7 @@ static void cs_release_csp(int i, int freefnpp)
             alive = FALSE;             /* cscope process no longer exists */
             break;
           }
-          mch_delay(50L, FALSE);           /* sleep 50ms */
+          os_delay(50L, FALSE);           /* sleep 50ms */
         }
       }
       if (alive)
diff --git a/src/main.c b/src/main.c
index e5a773e1d4..9cac0918ee 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1434,8 +1434,8 @@ scripterror:
       if (ga_grow(&global_alist.al_ga, 1) == FAIL
           || (p = vim_strsave((char_u *)argv[0])) == NULL)
         mch_exit(2);
-      if (parmp->diff_mode && mch_isdir(p) && GARGCOUNT > 0
-          && !mch_isdir(alist_name(&GARGLIST[0]))) {
+      if (parmp->diff_mode && os_isdir(p) && GARGCOUNT > 0
+          && !os_isdir(alist_name(&GARGLIST[0]))) {
         char_u      *r;
 
         r = concat_fnames(p, gettail(alist_name(&GARGLIST[0])), TRUE);
@@ -2115,7 +2115,7 @@ process_env (
   linenr_T save_sourcing_lnum;
   scid_T save_sid;
 
-  initstr = (char_u *)mch_getenv((char *)env);
+  initstr = (char_u *)os_getenv((char *)env);
   if (initstr != NULL && *initstr != NUL) {
     if (is_viminit)
       vimrc_found(NULL, NULL);
diff --git a/src/mark.c b/src/mark.c
index d153ab0a19..5e23e07857 100644
--- a/src/mark.c
+++ b/src/mark.c
@@ -480,7 +480,7 @@ static void fname2fnum(xfmark_T *fm)
       vim_strncpy(NameBuff, fm->fname, MAXPATHL - 1);
 
     /* Try to shorten the file name. */
-    mch_dirname(IObuff, IOSIZE);
+    os_dirname(IObuff, IOSIZE);
     p = shorten_fname(NameBuff, IObuff);
 
     /* buflist_new() will call fmarks_check_names() */
diff --git a/src/mbyte.c b/src/mbyte.c
index 95b28a6dad..8ac60ede11 100644
--- a/src/mbyte.c<