Singular

5.1.143 status

Syntax:

status ( link_expression, string_expression )

Type:

string

Syntax:

status ( link_expression, string_expression, string_expression )

Type:

int

Purpose:

returns the status of the link as asked for by the second argument. If a third argument is given, the result of the comparison to the status string is returned: (status(l,s1)==s2) is equivalent to status(l,s1,s2).
The following string expressions are allowed:

"name"

the name string given by the definition of the link (usually the filename)

"type"

returns "ASCII", "DBM" or "ssi"

"open"

returns "yes" or "no"

"openread"

returns "yes" or "no"

"openwrite"

returns "yes" or "no"

"read"

returns "ready" or "not ready"

"write"

returns "ready" or "not ready"

"mode"

returns (depending on the type of the link and its status) "","w","a","r" or "rw"

"exists"

returns "yes" or "no": existence of the filename for ASCII/ssi links

Syntax:

status ( list_expression, int_expression )

Type:

int

Purpose:

the list should be a list L of links, the second argument a timeout in 1/10 seconds. Returns

-2

select returns an error

-1

all links are closed/at eof

0

timeout

>0

(at least) L[i] is ready

Example:

link l=":w example.txt"; status(l,"write"); ==> not ready open(l); status(l,"write","ready"); ==> 1 close(l);