diff --git a/client/cs_apps.C b/client/cs_apps.C
index 7a4de3dc29..c078a3c15a 100644
--- a/client/cs_apps.C
+++ b/client/cs_apps.C
@@ -84,10 +84,6 @@ bool CLIENT_STATE::handle_running_apps() {
 // locally, false otherwise
 //
 bool CLIENT_STATE::input_files_available(RESULT* rp) {
-    if(rp==NULL) {
-        fprintf(stderr, "error: CLIENT_STATE.input_files_available: unexpected NULL pointer rp\n");
-        return false;
-    }
     WORKUNIT* wup = rp->wup;
     FILE_INFO* fip;
     unsigned int i;
diff --git a/client/cs_scheduler.C b/client/cs_scheduler.C
index b8bb76d7b1..8697ef591a 100644
--- a/client/cs_scheduler.C
+++ b/client/cs_scheduler.C
@@ -206,14 +206,7 @@ int CLIENT_STATE::make_scheduler_request(PROJECT* p, double work_req) {
     FILE* f = fopen(SCHED_OP_REQUEST_FILE, "wb");
     unsigned int i;
     RESULT* rp;
-    if(p==NULL) {
-        fprintf(stderr, "error: CLIENT_STATE.make_scheduler_request: unexpected NULL pointer p\n");
-        return ERR_NULL;
-    }
-    if(work_req<0) {
-        fprintf(stderr, "error: CLIENT_STATE.make_scheduler_request: negative work_req\n");
-        return ERR_NEG;
-    }
+
     if (!f) return ERR_FOPEN;
     fprintf(f,
         "<scheduler_request>\n"
diff --git a/client/file_xfer.C b/client/file_xfer.C
index 47cca052c2..fc12a6fc30 100644
--- a/client/file_xfer.C
+++ b/client/file_xfer.C
@@ -45,28 +45,12 @@ FILE_XFER::~FILE_XFER() {
 #if 0
 // Is there any reason to keep this around?
 int FILE_XFER::init_download(char* url, char* outfile) {
-    if(url==NULL) {
-        fprintf(stderr, "error: FILE_XFER.init_download: unexpected NULL pointer url\n");
-        return ERR_NULL;
-    }
-    if(outfile==NULL) {
-        fprintf(stderr, "error: FILE_XFER.init_download: unexpected NULL pointer outfile\n");
-        return ERR_NULL;
-    }
 
     return HTTP_OP::init_get(url, outfile, file_size);
 }
 
 // Is there any reason to keep this around?
 int FILE_XFER::init_upload(char* url, char* infile) {
-    if(url==NULL) {
-        fprintf(stderr, "error: FILE_XFER.init_upload: unexpected NULL pointer url\n");
-        return ERR_NULL;
-    }
-    if(outfile==NULL) {
-        fprintf(stderr, "error: FILE_XFER.init_upload: unexpected NULL pointer infile\n");
-        return ERR_NULL;
-    }
     return HTTP_OP::init_put(url, infile);
 }
 #endif
@@ -130,9 +114,6 @@ double FILE_XFER::elapsed_time() {
 // Create a new empty FILE_XFER_SET
 //
 FILE_XFER_SET::FILE_XFER_SET(HTTP_OP_SET* p) {
-    if(p==NULL) {
-        fprintf(stderr, "error: FILE_XFER_SET: unexpected NULL pointer p\n");
-    }
     http_ops = p;
 }
 
@@ -140,10 +121,7 @@ FILE_XFER_SET::FILE_XFER_SET(HTTP_OP_SET* p) {
 //
 int FILE_XFER_SET::insert(FILE_XFER* fxp) {
     int retval;
-    if(fxp==NULL) {
-        fprintf(stderr, "error: FILE_XFER_SET.insert: unexpected NULL pointer fxp\n");
-        return ERR_NULL;
-    }
+
     // record start time.
     // This could be made more accurate by omitting the connection
     // setup and initial request times.
@@ -159,10 +137,7 @@ int FILE_XFER_SET::insert(FILE_XFER* fxp) {
 //
 int FILE_XFER_SET::remove(FILE_XFER* fxp) {
     vector<FILE_XFER*>::iterator iter;
-    if(fxp==NULL) {
-        fprintf(stderr, "error: FILE_XFER_SET.remove: unexpected NULL pointer fxp\n");
-        return ERR_NULL;
-    }
+
     http_ops->remove(fxp);
 
     iter = file_xfers.begin();
diff --git a/client/hostinfo.C b/client/hostinfo.C
index 0081bdd30e..d8abae8edd 100644
--- a/client/hostinfo.C
+++ b/client/hostinfo.C
@@ -28,10 +28,7 @@
 //
 int HOST_INFO::parse(FILE* in) {
     char buf[256];
-    if(in==NULL) {
-	fprintf(stderr, "error: HOST_INFO.parse: unexpected NULL pointer in\n");
-        return ERR_NULL;
-    }
+
     memset(this, 0, sizeof(HOST_INFO));
     while (fgets(buf, 256, in)) {
         if (match_tag(buf, "</host_info>")) return 0;
@@ -60,10 +57,6 @@ int HOST_INFO::parse(FILE* in) {
 // Write the host information, usually to the client state XML file
 //
 int HOST_INFO::write(FILE* out) {
-    if(out==NULL) {
-        fprintf(stderr, "error: HOST_INFO.write: unexpected NULL pointer out\n");
-        return ERR_NULL;
-    }
     fprintf(out,
         "<host_info>\n"
         "    <timezone>%d</timezone>\n"
diff --git a/client/http.C b/client/http.C
index eb14275004..61dfa90c6c 100644
--- a/client/http.C
+++ b/client/http.C
@@ -48,15 +48,7 @@
 static void parse_url(char* url, char* host, char* file) {
     char* p;
     char buf[256];
-    if(url==NULL) {
-        fprintf(stderr, "error: parse_url: unexpected NULL pointer url\n");
-    }
-    if(host==NULL) {
-        fprintf(stderr, "error: parse_url: unexpected NULL pointer host\n");
-    }
-    if(file==NULL) {
-        fprintf(stderr, "error: parse_url: unexpected NULL pointer file\n");
-    }
+
     if (strncmp(url, "http://", 7) == 0) strcpy(buf, url+7);
     else strcpy(buf, url);
     p = strchr(buf, '/');
@@ -75,18 +67,6 @@ static void parse_url(char* url, char* host, char* file) {
 static void http_get_request_header(
     char* buf, char* host, char* file, double offset
 ) {
-    if(buf==NULL) {
-        fprintf(stderr, "error: http_get_request_header: unexpected NULL pointer buf\n");
-    }
-    if(host==NULL) {
-        fprintf(stderr, "error: http_get_request_header: unexpected NULL pointer host\n");
-    }
-    if(file==NULL) {
-        fprintf(stderr, "error: http_get_request_header: unexpected NULL pointer file\n");
-    }
-    if(offset<0) {
-        fprintf(stderr, "error: http_get_request_header: negative offset\n");
-    }
     if (offset) {
         sprintf(buf,
             "GET /%s HTTP/1.1\015\012"
@@ -115,15 +95,6 @@ static void http_get_request_header(
 // Prints an HTTP 1.1 HEAD request header into buf
 //
 static void http_head_request_header(char* buf, char* host, char* file) {
-    if(buf==NULL) {
-        fprintf(stderr, "error: http_head_request_header: unexpected NULL pointer buf\n");
-    }
-    if(host==NULL) {
-        fprintf(stderr, "error: http_head_request_header: unexpected NULL pointer host\n");
-    }
-    if(file==NULL) {
-        fprintf(stderr, "error: http_head_request_header: unexpected NULL pointer file\n");
-    }
     sprintf(buf,
         "HEAD /%s HTTP/1.1\015\012"
         "User-Agent: BOINC client\015\012"
@@ -141,18 +112,6 @@ static void http_head_request_header(char* buf, char* host, char* file) {
 static void http_post_request_header(
     char* buf, char* host, char* file, int size
 ) {
-    if(buf==NULL) {
-        fprintf(stderr, "error: http_post_request_header: unexpected NULL pointer buf\n");
-    }
-    if(host==NULL) {
-        fprintf(stderr, "error: http_post_request_header: unexpected NULL pointer host\n");
-    }
-    if(file==NULL) {
-        fprintf(stderr, "error: http_post_request_header: unexpected NULL pointer file\n");
-    }
-    if(size<0) {
-        fprintf(stderr, "error: http_post_request_header: negative size\n");
-    }
     sprintf(buf,
         "POST /%s HTTP/1.0\015\012"
         "Pragma: no-cache\015\012"
@@ -172,21 +131,6 @@ static void http_post_request_header(
 void http_put_request_header(
     char* buf, char* host, char* file, int size, int offset
 ) {
-    if(buf==NULL) {
-        fprintf(stderr, "error: http_put_request_header: unexpected NULL pointer buf\n");
-    }
-    if(host==NULL) {
-        fprintf(stderr, "error: http_put_request_header: unexpected NULL pointer host\n");
-    }
-    if(file==NULL) {
-        fprintf(stderr, "error: http_put_request_header: unexpected NULL pointer file\n");
-    }
-    if(size<0) {
-        fprintf(stderr, "error: http_put_request_header: negative size\n");
-    }
-    if(offset<0) {
-        fprintf(stderr, "error: http_put_request_header: negative offset\n");
-    }
     if (offset) {
         sprintf(buf,
             "PUT /%s HTTP/1.1\015\012"
@@ -263,18 +207,6 @@ int read_http_reply_header(int socket, HTTP_REPLY_HEADER& header) {
 //
 static int read_reply(int socket, char* buf, int len) {
     int i, n;
-    if(socket<0) {
-        fprintf(stderr, "error: read_reply: negative socket\n");
-        return ERR_NEG;
-    }
-    if(buf==NULL) {
-        fprintf(stderr, "error: read_reply: unexpected NULL pointer buf\n");
-        return ERR_NULL;
-    }
-    if(len<0) {
-        fprintf(stderr, "error: read_reply: negative len\n");
-        return ERR_NEG;
-    }
     for (i=0; i<len-1; i++) {
         n = recv(socket, buf+i, 1, 0);
         if (n != 1) break;
@@ -304,10 +236,6 @@ HTTP_OP::~HTTP_OP() {
 // Initialize HTTP HEAD operation to url
 //
 int HTTP_OP::init_head(char* url) {
-    if(url==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_head: unexpected NULL pointer url\n");
-        return ERR_NULL;
-    }
     parse_url(url, hostname, filename);
     NET_XFER::init(hostname, 80, HTTP_BLOCKSIZE);
     http_op_type = HTTP_OP_HEAD;
@@ -319,18 +247,6 @@ int HTTP_OP::init_head(char* url) {
 // Initialize HTTP GET operation to url
 //
 int HTTP_OP::init_get(char* url, char* out, bool del_old_file, double off) {
-    if(url==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_get: unexpected NULL pointer url\n");
-        return ERR_NULL;
-    }
-    if(out==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_get: unexpected NULL pointer out\n");
-        return ERR_NULL;
-    }
-    if(off<0) {
-        fprintf(stderr, "error: HTTP_OP.init_get: negative off\n"); 
-        return ERR_NEG;
-    }
     if (del_old_file) {
         unlink(out);
     }
@@ -348,18 +264,7 @@ int HTTP_OP::init_get(char* url, char* out, bool del_old_file, double off) {
 //
 int HTTP_OP::init_post(char* url, char* in, char* out) {
     int retval;
-    if(url==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_post: unexpected NULL pointer url\n");
-        return ERR_NULL;
-    }
-    if(in==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_post: unexpected NULL pointer in\n");
-        return ERR_NULL;
-    }
-    if(out==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_post: unexpected NULL pointer out\n");
-	return ERR_NULL;
-    }
+
     parse_url(url, hostname, filename);
     NET_XFER::init(hostname, 80, HTTP_BLOCKSIZE);
     strcpy(infile, in);
@@ -380,18 +285,7 @@ int HTTP_OP::init_post2(
     char* url, char* r1, char* in, double offset
 ) {
     int retval;
-    if(url==NULL) {
-        fprintf(stderr, "error: HTTP_OP.init_post2: unexpected NULL pointer url\n");
-        return ERR_NULL;
-    }
-    if(r1==NULL) {
-	fprintf(stderr, "error: HTTP_OP.init_post2: unexpected NULL pointer r1\n");
-        return ERR_NULL;
-    }
-    if(offset<0) {
-        fprintf(stderr, "error: HTTP_OP.init_post2: negative offset\n");
-        return ERR_NEG;
-    }
+
     parse_url(url, hostname, filename);
     NET_XFER::init(hostname, 80, HTTP_BLOCKSIZE);
     req1 = r1;
@@ -438,9 +332,6 @@ bool HTTP_OP::http_op_done() {
 }
 
 HTTP_OP_SET::HTTP_OP_SET(NET_XFER_SET* p) {
-    if(p==NULL) {
-        fprintf(stderr, "error: HTTP_OP_SET: unexpected NULL pointer p\n");
-    }
     net_xfers = p;
 }
 
@@ -448,10 +339,7 @@ HTTP_OP_SET::HTTP_OP_SET(NET_XFER_SET* p) {
 //
 int HTTP_OP_SET::insert(HTTP_OP* ho) {
     int retval;
-    if(ho==NULL) {
-        fprintf(stderr, "error: HTTP_OP_SET.insert: unexpected NULL pointer ho\n");
-        return ERR_NULL;
-    }
+
     retval = net_xfers->insert(ho);
     if (retval) return retval;
     http_ops.push_back(ho);
@@ -492,7 +380,7 @@ bool HTTP_OP_SET::poll() {
                 case HTTP_OP_POST:
                 //case HTTP_OP_PUT:
                     htp->http_op_state = HTTP_STATE_REQUEST_BODY;
-                    htp->file = fopen(htp->infile, "r");
+                    htp->file = fopen(htp->infile, "rb");
                     if (!htp->file) {
                         fprintf(stderr, "HTTP_OP: no input file %s\n", htp->infile);
                         htp->io_done = true;
@@ -522,7 +410,7 @@ bool HTTP_OP_SET::poll() {
                 // If there's a file we also want to send, then start transferring
                 // it, otherwise, go on to the next step
                 if (htp->infile && strlen(htp->infile) > 0) {
-                    htp->file = fopen(htp->infile, "r");
+                    htp->file = fopen(htp->infile, "rb");
                     if (!htp->file) {
                         fprintf(stderr, "HTTP_OP: no input2 file %s\n", htp->infile);
                         htp->io_done = true;
@@ -601,7 +489,7 @@ bool HTTP_OP_SET::poll() {
                     // Append to a file if it already exists, otherwise
                     // create a new one.  init_get should have already
                     // deleted the file if necessary
-                    htp->file = fopen(htp->outfile, "a");
+                    htp->file = fopen(htp->outfile, "ab");
                     if (!htp->file) {
                         fprintf(stderr,
                             "HTTP_OP: can't open output file %s\n",
@@ -654,10 +542,7 @@ bool HTTP_OP_SET::poll() {
 //
 int HTTP_OP_SET::remove(HTTP_OP* p) {
     vector<HTTP_OP*>::iterator iter;
-    if(p==NULL) {
-        fprintf(stderr, "error: HTTP_OP_SET.remove: unexpected NULL pointer p\n");
-        return ERR_NULL;
-    }
+
     net_xfers->remove(p);
 
     iter = http_ops.begin();
diff --git a/client/log_flags.C b/client/log_flags.C
index a30d9b9847..026ceae378 100644
--- a/client/log_flags.C
+++ b/client/log_flags.C
@@ -38,10 +38,7 @@ LOG_FLAGS::LOG_FLAGS() {
 //
 int LOG_FLAGS::parse(FILE* in) {
     char buf[256];
-    if(in==NULL) {
-        fprintf(stderr, "error: LOG_FLAGS.parse: unexpected NULL pointer in\n");
-        return ERR_NULL;
-    }
+
     fgets(buf, 256, in);
     if (!match_tag(buf, "<log_flags>")) return ERR_XML_PARSE;
     while (fgets(buf, 256, in)) {
diff --git a/client/net_stats.C b/client/net_stats.C
index 52a7942259..4675c24e6d 100644
--- a/client/net_stats.C
+++ b/client/net_stats.C
@@ -71,10 +71,6 @@ void NET_STATS::update(bool is_upload, double nbytes, double nsecs) {
 // Write XML based network statistics
 //
 int NET_STATS::write(FILE* out, bool to_server) {
-    if(out==NULL) {
-        fprintf(stderr, "error: NET_STATS.write: unexpected NULL pointer out\n");
-        return ERR_NULL;
-    }
     fprintf(out,
         "<net_stats>\n"
         "    <bwup>%f</bwup>\n"
@@ -97,10 +93,7 @@ int NET_STATS::write(FILE* out, bool to_server) {
 //
 int NET_STATS::parse(FILE* in) {
     char buf[256];
-    if(in==NULL) {
-        fprintf(stderr, "error: NET_STATS.parse: unexpected NULL pointer in\n");
-        return ERR_NULL;
-    }
+
     memset(this, 0, sizeof(NET_STATS));
     while (fgets(buf, 256, in)) {
         if (match_tag(buf, "</net_stats>")) return 0;
diff --git a/client/pers_file_xfer.C b/client/pers_file_xfer.C
index 8441b08c06..3d1fc0c615 100644
--- a/client/pers_file_xfer.C
+++ b/client/pers_file_xfer.C
@@ -228,10 +228,7 @@ bool PERS_FILE_XFER::poll(unsigned int now) {
 //
 int PERS_FILE_XFER::parse(FILE* fin) {
     char buf[256];
-    if(fin==NULL) {
-        fprintf(stderr, "error: PERS_FILE_XFER_SET.parse: unexpected NULL pointer fin\n");
-        return ERR_NULL;
-    }
+
     while (fgets(buf, 256, fin)) {
         if (match_tag(buf, "</persistent_file_xfer>")) return 0;
         else if (parse_int(buf, "<num_retries>", nretry)) continue;
@@ -245,10 +242,6 @@ int PERS_FILE_XFER::parse(FILE* fin) {
 // Write XML information about a particular persistent file transfer
 //
 int PERS_FILE_XFER::write(FILE* fout) {
-    if (fout==NULL) {
-        fprintf(stderr, "error: PERS_FILE_XFER_SET.write: unexpected NULL pointer fout\n");
-        return ERR_NULL;
-    }
     fprintf(fout,
 	"    <persistent_file_xfer>\n"
 	"        <num_retries>%d</num_retries>\n"
@@ -261,9 +254,6 @@ int PERS_FILE_XFER::write(FILE* fout) {
 }
 
 PERS_FILE_XFER_SET::PERS_FILE_XFER_SET(FILE_XFER_SET* p) {
-    if(p==NULL) {
-        fprintf(stderr, "error: PERS_FILE_XFER_SET: unexpected NULL pointer p\n");
-    }
     file_xfers = p;
 }
 
diff --git a/client/time_stats.C b/client/time_stats.C
index b879e0c3cd..a2b55a3552 100644
--- a/client/time_stats.C
+++ b/client/time_stats.C
@@ -106,10 +106,7 @@ int TIME_STATS::write(FILE* out, bool to_server) {
 //
 int TIME_STATS::parse(FILE* in) {
     char buf[256];
-    if(in==NULL) {
-        fprintf(stderr, "error: TIME_STATS.parse: unexpected NULL pointer in\n");
-        return ERR_NULL;
-    }
+
     while (fgets(buf, 256, in)) {
         if (match_tag(buf, "</time_stats>")) return 0;
         else if (parse_int(buf, "<last_update>", last_update)) continue;