diff --git a/usr.bin/sed/main.c b/usr.bin/sed/main.c index 8d4fe95a33d..049d2ea1e83 100644 --- a/usr.bin/sed/main.c +++ b/usr.bin/sed/main.c @@ -338,18 +338,35 @@ mf_fgets(SPACE *sp, enum e_spflag spflag) if (infile != NULL) { fclose(infile); if (*oldfname != '\0') { - if (rename(fname, oldfname) != 0) { + /* if there was a backup file, remove it */ + unlink(oldfname); + /* + * Backup the original. Note that hard links + * are not supported on all filesystems. + */ + if ((link(fname, oldfname) != 0) && + (rename(fname, oldfname) != 0)) { warn("rename()"); - unlink(tmpfname); + if (*tmpfname) + unlink(tmpfname); exit(1); } *oldfname = '\0'; } if (*tmpfname != '\0') { if (outfile != NULL && outfile != stdout) - fclose(outfile); + if (fclose(outfile) != 0) { + warn("fclose()"); + unlink(tmpfname); + exit(1); + } outfile = NULL; - rename(tmpfname, fname); + if (rename(tmpfname, fname) != 0) { + /* this should not happen really! */ + warn("rename()"); + unlink(tmpfname); + exit(1); + } *tmpfname = '\0'; } outfname = NULL;