build

bld

1998 12-06

NAME

SYNOPSIS

OPTIONS

• -d
  Enable debugging messages. This may be useful in attempting to analyze problems.
• -? {true|false}
  Print help information and exit. The default is false.
• -V {true|false}
  Print verbose debugging information. The default is false.
• -d {true|false}
  Print debugging information. The default is false.
• -f filename
  Read the build description from filename. The default is ./.bld.
• -h {true|false}
  Print help information and exit. The default is false.
• -k {true|false}
  Continue building even in case of failures. The default is false.
• -n {true|false}
  Avoid execution of commands. The default is false.
• -q {true|false}
  Suppress the printing of commands prior to execution. The default is false.
• -s {true|false}
  Suppress the printing of the output of commands. The default is false.
• -u {true|false}
  Rebuild all targets unconditionally (i.e., regardless of their modification time). The default is false.
• -v {true|false}
  Print version information and exit. The default is false.

DESCRIPTION

ENVIRONMENT

• BLD_DEBUG
  Enables printing of debugging information when its value is true.
• BLD_FILE
  Specifies the build description file. Relative path-names are evaluated with respect to the current directory.
• BLD_IGNORE_SYSTEM_FAILURES
  Enables persistence in the face of failures of system commands when its value is true. Normally, build stops all work when a command fails.
• BLD_IGNORE_TARGET_FAILURES
  Enables persistence in the face of failures of build targets when its value is true. Normally, build stops all work when a target fails.
• BLD_NO_EXECUTION
  Disables execution of commands when its value is true
• BLD_PERSIST
  Enables persistence in the face of failures when its value is true. Normally, build stops all work when anything fails.
• BLD_PRINT_HELP
  Enables printing of help information when its value is true. This results in build exiting as soon as the help information is printed, which lowers its usefulness as an environment variable.
• BLD_PRINT_VERSION
  Enables printing of version information when its value is true. This results in build exiting as soon as the version information is printed, which lowers its usefulness as an environment variable.
• BLD_QUIET
  Disables printing of the command prior to execution when its value is true.
• BLD_SILENT
  Disables printing of the output from a command when its value is true.
• BLD_UNCONDITIONAL_REBUILD
  Disables the use of file modification times in the build avoidance algorithm when its value is true.
• BLD_VERBOSE
  Enables printing of debugging information when its value is true.

EXIT STATUS

• 0 Successful completion.
• -1 One or more targets failed.

FILES

• ./.bld
  Contains the default build rules.

NOTES

To support the common use of the character '.' as a separator between file names and extensions, its use as a meta-character in regular expressions has been disabled. In its place, the character range [!-~] is functionally equivalent.

Since all built-in functions are treated equally and variable evaluation is performed for all, the directory, file, and targets for nested builds via build can be specified using variables. Thus, all three can be determined at build time.

DIAGNOSTICS

Handling of variable expansion in naked strings is not graceful. Particularly the string $(0).cc will not evaluate properly because the parser is expected white-space after naked variables. "$(0).cc" is required to build a string consisting of ".cc" appended to the contents of the variable 0.

Unquoted arguments should not contain meta-characters, such as ':'. If the arguments do contain such meta-characters, the arguments should be protected by single- or double-quotes.

The parser reports errors at the line where the parser failed, which may not be the line which caused the error, and provides no explanation about the cause of the error.

BUGS

Line continuation (e.g. '\\' at the end of the line) is not implemented.

System commands are not currently parallelized.