1 files changed, 41 insertions, 9 deletions

diff --git a/src/build.l b/src/build.l
index 49275c8..15c4003 100644
--- a/src/build.l
+++ b/src/build.l
@@ -9,6 +9,7 @@ std::string strbuf;
 
 %x strsq
 %x strdq
+%x cmdstr
 %x comment
 %option noyywrap nounput batch debug
 
@@ -78,6 +79,10 @@ std::string strbuf;
         BEGIN( strsq );
         strbuf = "";
 }
+\`                                                                      {
+        BEGIN( cmdstr );
+        strbuf = "";
+}
 
 <strdq>[^\\\n\"]+                                       {
         strbuf += yytext;
@@ -87,15 +92,20 @@ std::string strbuf;
         strbuf += yytext;
 }
 
-<strdq,strsq>\\n                                        strbuf += "\n";
-<strdq,strsq>\\t                                        strbuf += "\t";
-<strdq,strsq>\\r                                        strbuf += "\r";
-<strdq,strsq>\\b                                        strbuf += "\b";
-<strdq,strsq>\\f                                        strbuf += "\f";
-<strdq,strsq>\\\\                                       strbuf += "\\";
-<strdq,strsq>\\\"                                       strbuf += "\"";
-<strdq,strsq>\\\'                                       strbuf += "\'";
-<strdq,strsq>\\.                                        bld.error( yylloc, "Invalid escape sequence.");
+<cmdstr>[^\\\n\`]+                                      {
+        strbuf += yytext;
+}
+
+<strdq,strsq,cmdstr>\\n                         strbuf += "\n";
+<strdq,strsq,cmdstr>\\t                         strbuf += "\t";
+<strdq,strsq,cmdstr>\\r                         strbuf += "\r";
+<strdq,strsq,cmdstr>\\b                         strbuf += "\b";
+<strdq,strsq,cmdstr>\\f                         strbuf += "\f";
+<strdq,strsq,cmdstr>\\\\                        strbuf += "\\";
+<strdq,strsq,cmdstr>\\\"                        strbuf += "\"";
+<strdq,strsq,cmdstr>\\\'                        strbuf += "\'";
+<strdq,strsq,cmdstr>\\\`                        strbuf += "`";
+<strdq,strsq,cmdstr>\\.                 bld.error( yylloc, "Invalid escape sequence.");
 
 <strdq>\"                                                       {
         BEGIN( INITIAL );
@@ -109,6 +119,28 @@ std::string strbuf;
         return STRING;
 }
 
+<cmdstr>\`                                                      {
+        BEGIN( INITIAL );
+        FILE *fpg = popen( strbuf.c_str(), "r" );
+        strbuf = "";
+        for(;;)
+        {
+                char buf[1024];
+                int nRead = fread( buf, 1, 1024, fpg );
+                if( nRead == 0 ) break;
+                for( int j = 0; j < nRead; j++ )
+                {
+                        if( buf[j] == '\n' || buf[j] == '\r' )
+                                buf[j] = ' ';
+                }
+                strbuf.append( buf, nRead );
+                if( nRead < 1024 ) break;
+        }
+        yylval->strval = stringdup( strbuf.c_str() );
+        pclose( fpg );
+        return STRING;
+}
+
 .                                                                       {
         char buf[] = {"Character x is out of place"};
         buf[10] = yytext[0];