Difference between revisions of "sysutils"

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m (Improved English grammar)
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== Notable functionality ==
 
== Notable functionality ==
 
 
* [[Format function|<syntaxhighlight lang="pascal" inline>format</syntaxhighlight>]]
 
* [[Format function|<syntaxhighlight lang="pascal" inline>format</syntaxhighlight>]]
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* [[Executing External Programs#SysUtils.ExecuteProcess|<syntaxhighlight lang="pascal" inline>executeProcess</syntaxhighlight> for executing external programs]]
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* several routines ensuring productive use of [[TDateTime|<syntaxhighlight lang="pascal" inline>tDateTime</syntaxhighlight>]]
 
* {{Doc|package=RTL|unit=sysutils|identifier=typehelpers|text=type helpers for all basic data types}}
 
* {{Doc|package=RTL|unit=sysutils|identifier=typehelpers|text=type helpers for all basic data types}}
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* [[FreeAndNil|<syntaxhighlight lang="pascal" inline>freeAndNil</syntaxhighlight>]]
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* routines to access [[Command line parameters and environment variables#Environment variables|environment variables]]
  
 
== Caveats ==
 
== Caveats ==
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{{Doc|package=RTL|unit=system|identifier=runtimeerrors|text=If the <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> unit is included}}, all [[runtime error|run-time errors]] become [[Exceptions|exceptions]], which virtually forces you to use a [[Compiler Mode|compiler mode]] (or [[modeswitch|mode switch]]) that allows exception treatment.
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To catch an exception by its name you will need to include <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> in every unit that may throw an exception, even though the unit itself does not use any of the included system utilities.
  
{{Doc|package=RTL|unit=system|identifier=runtimeerrors|text=If the <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> unit is included}}, all [[runtime error|run-time errors]] become [[Exceptions|exceptions]], which virtually forces you to use a [[Compiler Mode|compiler mode]] (or [[modeswitch|mode switch]]) that allows exception treatment.
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If [[Size Matters|size matters]], using <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> is by design not the smartest choice.
You will need to include <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> in every unit that may throw an exception, even though the unit itself does not use any of the included system utilities.
 
  
 
== See also ==
 
== See also ==
 
 
* {{Doc|package=RTL|unit=sysutils|text=<syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> reference}}
 
* {{Doc|package=RTL|unit=sysutils|text=<syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> reference}}
 
* [http://docwiki.embarcadero.com/Libraries/Sydney/en/System.SysUtils Delphi’s <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> unit]
 
* [http://docwiki.embarcadero.com/Libraries/Sydney/en/System.SysUtils Delphi’s <syntaxhighlight lang="pascal" inline>sysUtils</syntaxhighlight> unit]
* [[libc|<syntaxhighlight lang="pascal" inline>libc</syntaxhighlight>]] <!-- similar in design -->
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* [[libc library|<syntaxhighlight lang="c" inline>libc</syntaxhighlight> library]] <!-- similar in design -->
 
* [[System unit|<syntaxhighlight lang="pascal" inline>system</syntaxhighlight> unit]]
 
* [[System unit|<syntaxhighlight lang="pascal" inline>system</syntaxhighlight> unit]]

Revision as of 00:22, 23 January 2021

English (en) Esperanto (eo) français (fr)

The unit sysUtils shipped with the FPC’s default run-time library provides many system utilities. It attempts to be as compatible to Delphi’s sysUtils unit as possible. However, the FPC version is available on all platforms that the FPC supports. It does not contain any Windows-related routines or other highly platform-specific functionality.

Notable functionality

Caveats

If the sysUtils unit is included, all run-time errors become exceptions, which virtually forces you to use a compiler mode (or mode switch) that allows exception treatment. To catch an exception by its name you will need to include sysUtils in every unit that may throw an exception, even though the unit itself does not use any of the included system utilities.

If size matters, using sysUtils is by design not the smartest choice.

See also