### 3.1.7 Startup sequence

On start-up, SINGULAR

1. loads the library `standard.lib` (provided the `--no-stdlib` option was not given),

2. searches the current directory and then the home directory of the user, and then all directories contained in the library `SearchPath` (see Loading a library for more info on `SearchPath`) for a file named `.singularrc` and executes it, if found (provided the `--no-rc` option was not given),

3. executes the string specified with the `--execute` command line option,

4. executes the files `file1`, `file2` ... (given on the command line) in that order.

Note: `.singularrc` file(s) are an appropriate place for setting some default values of (command-line) options.

For example, a system administrator might remove the locally installed HTML version of the manual and put a `.singularrc` file with the following content

    if (system("version") >= 1306) // assure backwards-compatibility
    {
      system("--allow-net", 1);
    }; // the last semicolon is important: otherwise no ">", but "." prompt

in the directory containing the SINGULAR libraries, thereby allowing to fetch the HTML on-line help from the WWW home-site of SINGULAR.

On the other hand, a single user might put a `.singularrc` with the following content

    if (system("version") >= 1306) // assure backwards-compatibility
    {
      if (! system("--emacs"))
      {
        // set default browser to info, unless we run within emacs
        system("--browser", "info");
      }
    }; // the last semicolon is important: otherwise no ">", but "." prompt

in his home directory, which sets the default help browser to `info` (unless SINGULAR is run within emacs) and thereby prevents the execution of the"global" `.singularrc` file installed by the system administrator (since the `.singularrc` file of the user is found before the "global" `.singularrc` file installed by the system administrator).

User manual for Singular version 4.4.1, 2025, generated by texi2html.