use tmpfile() and revert my previous changes... convert() belongs here
diff --git a/Makefile b/Makefile
index ed59deb..3141191 100644
--- a/Makefile
+++ b/Makefile
@@ -236,17 +236,18 @@
 LIBBB	  = libbb
 LIBBB_LIB = libbb.a
 LIBBB_CSRC= ask_confirmation.c check_wildcard_match.c chomp.c \
-concat_path_file.c copy_file.c copy_file_chunk.c create_path.c daemon.c \
-deb_extract.c device_open.c error_msg.c error_msg_and_die.c find_mount_point.c \
-find_pid_by_name.c find_root_device.c full_read.c full_write.c \
-get_ar_headers.c get_console.c get_last_path_component.c get_line_from_file.c \
-gz_open.c human_readable.c inode_hash.c isdirectory.c kernel_version.c loop.c \
-mode_string.c module_syscalls.c mtab.c mtab_file.c my_getgrnam.c my_getgrgid.c \
-my_getpwnam.c my_getpwnamegid.c my_getpwuid.c parse_mode.c parse_number.c \
-perror_msg.c perror_msg_and_die.c print_file.c process_escape_sequence.c \
-recursive_action.c safe_read.c safe_strncpy.c seek_ared_file.c syscalls.c \
-syslog_msg_with_name.c time_string.c trim.c untar.c unzip.c vdprintf.c \
-verror_msg.c vperror_msg.c wfopen.c xfuncs.c xgetcwd.c xregcomp.c
+concat_path_file.c copy_file.c copy_file_chunk.c create_path.c \
+daemon.c deb_extract.c device_open.c error_msg.c error_msg_and_die.c \
+find_mount_point.c find_pid_by_name.c find_root_device.c full_read.c \
+full_write.c get_ar_headers.c get_console.c get_last_path_component.c \
+get_line_from_file.c gz_open.c human_readable.c inode_hash.c isdirectory.c \
+kernel_version.c loop.c mode_string.c module_syscalls.c mtab.c mtab_file.c \
+my_getgrnam.c my_getgrgid.c my_getpwnam.c my_getpwnamegid.c my_getpwuid.c \
+parse_mode.c parse_number.c perror_msg.c perror_msg_and_die.c print_file.c \
+process_escape_sequence.c recursive_action.c safe_read.c safe_strncpy.c \
+seek_ared_file.c syscalls.c syslog_msg_with_name.c time_string.c trim.c \
+untar.c unzip.c vdprintf.c verror_msg.c vperror_msg.c wfopen.c xfuncs.c \
+xgetcwd.c xregcomp.c
 
 LIBBB_OBJS=$(patsubst %.c,$(LIBBB)/%.o, $(LIBBB_CSRC))
 LIBBB_CFLAGS = -I$(LIBBB)
diff --git a/coreutils/dos2unix.c b/coreutils/dos2unix.c
index b2dcfd9..8308c41 100644
--- a/coreutils/dos2unix.c
+++ b/coreutils/dos2unix.c
@@ -27,9 +27,93 @@
  * See the COPYING file for license information.
  */
 
+#include <string.h>
 #include <getopt.h>
 #include "busybox.h"
 
+// if fn is NULL then input is stdin and output is stdout
+extern int convert(char *fn, int ConvType) {
+	char c;
+	char *tempFn = NULL;
+	FILE *in = stdin, *out = stdout;
+
+	if (fn != NULL) {
+		if ((in = wfopen(fn, "r")) == NULL) {
+			return -1;
+		}
+		if ((out = tmpfile()) == NULL) {
+			perror_msg(NULL);
+			return -2;
+		}
+	}
+
+	while ((c = fgetc(in)) != EOF) {
+		if (c == '\r') {
+			if ((ConvType == CT_UNIX2DOS) && (fn != NULL)) {
+				// file is alredy in DOS format so it is not necessery to touch it
+				if (fclose(in) < 0 || fclose(out) < 0) {
+					perror_msg(NULL);
+					return -2;
+				}
+				return 0;
+			}
+			if (!ConvType)
+				ConvType = CT_DOS2UNIX;
+			break;
+		}
+		if (c == '\n') {
+			if ((ConvType == CT_DOS2UNIX) && (fn != NULL)) {
+				// file is alredy in UNIX format so it is not necessery to touch it
+				if ((fclose(in) < 0) || (fclose(out) < 0)) {
+					perror_msg(NULL);
+					return -2;
+				}
+				return 0;
+			}
+			if (!ConvType) {
+				ConvType = CT_UNIX2DOS;
+			}
+			if (ConvType == CT_UNIX2DOS) {
+				fputc('\r', out);
+			}
+			fputc('\n', out);
+			break;
+		}
+		fputc(c, out);
+	}
+	if (c != EOF)
+		while ((c = fgetc(in)) != EOF) {
+			if (c == '\r')
+				continue;
+			if (c == '\n') {
+				if (ConvType == CT_UNIX2DOS)
+					fputc('\r', out);
+				fputc('\n', out);
+				continue;
+			}
+		fputc(c, out);
+	}
+
+	if (fn != NULL) {
+	    if (fclose(in) < 0 || fclose(out) < 0 || 
+		    (in = fopen(tempFn, "r")) == NULL || (out = fopen(fn, "w")) == NULL) {
+			perror_msg(NULL);
+			return -2;
+	    }
+
+	    while ((c = fgetc(in)) != EOF) {
+			fputc(c, out);
+		}
+
+	    if ((fclose(in) < 0) || (fclose(out) < 0)) {
+			perror_msg(NULL);
+			return -2;
+	    }
+	}
+
+	return 0;
+}
+
 int dos2unix_main(int argc, char *argv[]) {
 	int ConvType = CT_AUTO;
 	int o;
diff --git a/dos2unix.c b/dos2unix.c
index b2dcfd9..8308c41 100644
--- a/dos2unix.c
+++ b/dos2unix.c
@@ -27,9 +27,93 @@
  * See the COPYING file for license information.
  */
 
+#include <string.h>
 #include <getopt.h>
 #include "busybox.h"
 
+// if fn is NULL then input is stdin and output is stdout
+extern int convert(char *fn, int ConvType) {
+	char c;
+	char *tempFn = NULL;
+	FILE *in = stdin, *out = stdout;
+
+	if (fn != NULL) {
+		if ((in = wfopen(fn, "r")) == NULL) {
+			return -1;
+		}
+		if ((out = tmpfile()) == NULL) {
+			perror_msg(NULL);
+			return -2;
+		}
+	}
+
+	while ((c = fgetc(in)) != EOF) {
+		if (c == '\r') {
+			if ((ConvType == CT_UNIX2DOS) && (fn != NULL)) {
+				// file is alredy in DOS format so it is not necessery to touch it
+				if (fclose(in) < 0 || fclose(out) < 0) {
+					perror_msg(NULL);
+					return -2;
+				}
+				return 0;
+			}
+			if (!ConvType)
+				ConvType = CT_DOS2UNIX;
+			break;
+		}
+		if (c == '\n') {
+			if ((ConvType == CT_DOS2UNIX) && (fn != NULL)) {
+				// file is alredy in UNIX format so it is not necessery to touch it
+				if ((fclose(in) < 0) || (fclose(out) < 0)) {
+					perror_msg(NULL);
+					return -2;
+				}
+				return 0;
+			}
+			if (!ConvType) {
+				ConvType = CT_UNIX2DOS;
+			}
+			if (ConvType == CT_UNIX2DOS) {
+				fputc('\r', out);
+			}
+			fputc('\n', out);
+			break;
+		}
+		fputc(c, out);
+	}
+	if (c != EOF)
+		while ((c = fgetc(in)) != EOF) {
+			if (c == '\r')
+				continue;
+			if (c == '\n') {
+				if (ConvType == CT_UNIX2DOS)
+					fputc('\r', out);
+				fputc('\n', out);
+				continue;
+			}
+		fputc(c, out);
+	}
+
+	if (fn != NULL) {
+	    if (fclose(in) < 0 || fclose(out) < 0 || 
+		    (in = fopen(tempFn, "r")) == NULL || (out = fopen(fn, "w")) == NULL) {
+			perror_msg(NULL);
+			return -2;
+	    }
+
+	    while ((c = fgetc(in)) != EOF) {
+			fputc(c, out);
+		}
+
+	    if ((fclose(in) < 0) || (fclose(out) < 0)) {
+			perror_msg(NULL);
+			return -2;
+	    }
+	}
+
+	return 0;
+}
+
 int dos2unix_main(int argc, char *argv[]) {
 	int ConvType = CT_AUTO;
 	int o;