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Via file syntax rules

C.2 Via file syntax rules

Via files must conform to some syntax rules.

  • A via file is a text file containing a sequence of words. Each word in the text file is converted into an argument string and passed to the tool.

  • Words are separated by whitespace, or the end of a line, except in delimited strings, for example:

    --bigend --reduce_paths (two words)

    --bigend--reduce_paths (one word)

  • The end of a line is treated as whitespace, for example:


    This is equivalent to:

    --bigend --reduce_paths

  • Strings enclosed in quotation marks ("), or apostrophes (') are treated as a single word. Within a quoted word, an apostrophe is treated as an ordinary character. Within an apostrophe delimited word, a quotation mark is treated as an ordinary character.

    Use quotation marks to delimit filenames or path names that contain spaces, for example:

    --errors C:\My Project\errors.txt (three words)

    --errors "C:\My Project\errors.txt" (two words)

    Use apostrophes to delimit words that contain quotes, for example:

    -DNAME='"ARM Compiler"' (one word)

  • Characters enclosed in parentheses are treated as a single word, for example:

    --option(x, y, z) (one word)

    --option (x, y, z) (two words)

  • Within quoted or apostrophe delimited strings, you can use a backslash (\) character to escape the quote, apostrophe, and backslash characters.

  • A word that occurs immediately next to a delimited word is treated as a single word, for example:


    This is treated as the single word:


  • Lines beginning with a semicolon (;) or a hash (#) character as the first nonwhitespace character are comment lines. A semicolon or hash character that appears anywhere else in a line is not treated as the start of a comment, for example:

    -o objectname.axf      ;this is not a comment

    A comment ends at the end of a line, or at the end of the file. There are no multi-line comments, and there are no part-line comments.

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