NAME

       asn1c - ASN.1 Compiler

SYNOPSIS

       asn1c [-E [-F] | -P | -R]
             [-Sdir] [-X]
             [-Wdebug-...] [-foption] [-gen-option] [-pdu={all|auto|Type}]
             [-print-option]
             infile...

DESCRIPTION

       asn1c  compiles  ASN.1  specifications  into a set of target language (C/C++) encoders and
       decoders for BER, DER, PER, XER and other encoding rules.

OPTIONS

       Overall Options
              -E -F -P -R -S directory -X

       Warning Options
              -Werror -Wdebug-lexer -Wdebug-fixer -Wdebug-compiler

       Language Options
              -fbless-SIZE    -fcompound-names    -findirect-choice    -fknown-extern-type=<name>
              -fnative-types -fno-constraints -fno-include-deps -funnamed-unions -fskeletons-copy

       Codecs Generation Options
              -gen-PER -pdu={all|auto|Type}

       Output Options
              -print-constraints -print-lines

OVERALL OPTIONS

       -E     Stop  after  the parsing stage and print the reconstructed ASN.1 specification code
              to the standard output.

       -F     Used together with -E, instructs the compiler to stop after the ASN.1  syntax  tree
              fixing stage and dump the reconstructed ASN.1 specification to the standard output.

       -P     Dump  the  compiled  output  to  the standard output instead of creating the target
              language files on disk.

       -R     Restrict the compiler to generate only the ASN.1 tables, omitting the usual support
              code.

       -S directory
              Use the specified directory with ASN.1 skeleton files.

       -X     Generate an XML DTD schema for the specified ASN.1 files.

WARNING OPTIONS

       -Werror
              Treat warnings as errors; abort if any warning is produced.

       -Wdebug-lexer
              Enable lexer debugging during the ASN.1 parsing stage.

       -Wdebug-fixer
              Enable ASN.1 syntax tree fixer debugging during the fixing stage.

       -Wdebug-compiler
              Enable debugging during the actual compile time.

LANGUAGE OPTIONS

       -fbless-SIZE
              Allow  SIZE()  constraint  for  INTEGER, ENUMERATED, and other types for which this
              constraint is normally prohibited by the standard. This is  a  violation  of  ASN.1
              standard, and the compiler may fail to produce a meaningful code.

       -fcompound-names
              Using  this  option  prevents  name  collisions  in the target source code by using
              complex names for target language structures. (Name collisions  may  occur  if  the
              ASN.1 module reuses the same identifiers in multiple contexts).

       -findirect-choice
              When  generating  code  for  a  CHOICE type, compile the CHOICE members as indirect
              pointers instead of declaring them inline. Consider using this option together with
              -fno-include-deps to prevent circular references.

       -fknown-extern-type=<name>
              Pretend  the  specified type is known. The compiler will assume the target language
              source files for the given type have been provided manually.

       -fnative-types
              Use the native machine's data types (int, double) whenever possible, instead of the
              compound INTEGER_t, ENUMERATED_t and REAL_t types.

       -fno-constraints
              Do  not  generate  ASN.1  subtype constraint checking code. This may make a shorter
              executable.

       -fno-include-deps
              Do not generate courtesy #include lines for non-critical type dependencies.   Helps
              prevent namespace collisions.

       -funnamed-unions
              Enable unnamed unions in the definitions of target language's structures.

       -fskeletons-copy
              Copy support files (skeletons) rather than symlink them.

CODECS GENERATION OPTIONS

       -gen-PER
              Generate Packed Encoding Rules (PER) support code.

       -pdu={all|auto|Type}
              Create   a  PDU  table  for  specified  types,  or  discover  Protocol  Data  Units
              automatically. In case of -pdu=all, all ASN.1 types defined  in  all  modules  will
              form  a PDU table. In case of -pdu=auto, all types not referenced by any other type
              will form a PDU table.  If Type is an ASN.1 type identifier, it is added to  a  PDU
              table.  The last form may be specified multiple times to add any number of PDUs.

OUTPUT OPTIONS

       -print-constraints
              When  -EF  are  also  specified,  this  option  forces  the compiler to explain its
              internal understanding of subtype constraints.

       -print-lines
              Generate "-- #line" comments in -E output.

SEE ALSO

       unber(1), enber(1)

AUTHORS

       Lev Walkin <vlm@lionet.info>